Introduction

Empirical evidence has suggested that excellent customer-focused service is a successful differentiation strategy (Copeland & Mahsud, 2020), to the point that service quality has gained the status of a key strategy for business growth (Poor et al., 2016). For this reason, Desfitrina et al. (2019) argue that customer service is a tool of differentiation and competitiveness for companies, as it promotes consumer purchase and satisfaction (Angelova & Zekiri, 2011; Yeboah & Ewur, 2014).

However, although it is impossible to thrive and conquer the market without satisfied customers, companies of all sizes still provide a superficial service and/or a service that falls short of market expectations (Bengtsson et al., 2020), usually based on standardized procedures and not always related to consumer expectations and requirements. This situation makes losing customers an easy task in an increasingly competitive market (Kotler & Keller, 2012).

This discussion of the importance and strategic role of customer service also extends to retail companies, because according to Rodríguez and Figueroa (2019), it is common for companies in this industry to receive numerous complaints about the service offered to consumers. In addition, Conceição et al. (2021) describe that in Brazil there is a high level of dissatisfaction with the customer service quality provided by retail companies and that national consumers are willing to pay higher prices in exchange for better service.

Therefore, the present work intends to answer the following problem: how does customer service give a retail company a competitive advantage? To answer the problem presented, this study sought to analyze customer service as an element of competitive advantage in a retail company in the optical industry. Specifically, this study analyzed customer loyalty actions, strategic customer service activities and customer service as an instrument for an organizational competitiveness.

To achieve the proposed objectives, a single case study was performed in a retailer of optical articles, which started its activities in the virtual environment, became known in the digital environment for the attention dedicated to customer service, doubled its revenues in one year, expanded to a physical store and began selling its products in other states and countries.

In this regard, it should be noted that retail companies in Brazil play an important role in the socioeconomic field, because according to the study "O Papel do Varejo na Economia Brasileira" (SBVC, 2021), this sector is one of the most important for the economy, with growth above the national GDP average. The same study shows that in 2019 this sector generated more than BRL 3 billion and employed more than 8.5 million people, representing 26% of formal jobs in the country.

Among the reasons for analyzing an optical retailer, it is worth noting that this sector has an estimated growth rate of over 8.9% in 2022 compared to 2021 (Abióptica, 2022) and that in the first quarter of 2019, this industry invoiced BRL 23.2 billion, representing a growth of 3.7% compared to 2018 (Abióptica, 2019). Additionally, according to the "Pesquisa Mercado Óptico Brasileiro 2022", the differential for the high revenues of companies in this sector is the service and the relationship with the consumer (ssÓtica, 2022).

Aside from the economic relevance and importance of customer service in companies in the optical sector, a brief search of the SPELL and Scielo databases found no similar studies that directly address the relationship between customer service and competitive advantage. Furthermore, studies that analyze, in an integrated way, the elements of customer service as a competitive advantage in retail and optical companies were not noticed, which reinforces the theoretical gap for this research.

On the other hand, studies dealing with aspects related to customer service in physical and/or digital media tend to approach it from the perspective of the shopping experience and customer behavior, usually with quantitative analysis and from the buyers’ perspective (Queiroz et al. al., 2016; Meenakshy & Srivastava, 2022). In this context, this research differs by conducting a qualitative analysis that combines a manager's and customer's perceptions and provides more detailed results and insights that can help other organizations optimize customer service practices as an element of competitive advantage.

Customer service as a competitive advantage: loyalty, strategic actions and organizational competitiveness

Ordoñez-Velez and Zaldumbide-Peralvo (2020) explain that a competitive advantage is any characteristic of a company, country or person that distinguishes them from others and puts them in a position of economic superiority. On this topic, Martínez (2016) argues that customer service is one of the most important mechanisms to gain competitive advantage in organizations, especially when companies recognize that consumers are the most important asset of the organization and that meeting their wants and needs is a basic requirement for corporate growth and consolidation.

This is not a new insight, as Donaldson (1995) had already recognized that one of the best ways to grow and stand out in the market is to serve customers better than the competition. On this topic, Detzel and Desatnick (1995) postulated that customer service is a key element in creating business value, differentiation and in the success of any organization (Azigwe et al., 2016).

On the other hand, Copeland and Mahsud (2020) report that despite the recognition that customer service is a tool of competitive advantage, there are companies that continue in serving them with negligence (Darmawan et al., 2017). In this theoretical path, Silva-Treviño et al. (2021) explain that the quality of this service has a significant impact on the permanence or evasion of buyers in an organization.

Furthermore, Yeboah and Ewur (2014) note that by ensuring the quality of customer service, companies lay the foundation for competitive advantage and attract customers who prefer them in purchasing situations. These authors argue that the quality of customer service and service delivery is an important element in the success and competitive advantage of a company, especially if the organization can meet the standards and expectations of its customers.

Moreover, researchers such as Chandra and Kumar (2000) have stated that customer service is an organizational competitiveness tool that makes the company stand out to consumers, promotes customer satisfaction, and helps define the structure, processes, and products for success (Poor et al., 2013).

In this context, Zilber and Lazarini (2005) noted that one of the ways to make customer service a tool of competitive advantage is through consumer loyalty. Indeed, intense competition in the retail market underscores the need to retain customers as a strategy to maintain competitive advantage (Liu-Thompkins et al., 2022).

On this topic, Ribeiro (2007) presents some tools that should be used to build customer loyalty, namely:

· Empathy: the ability to put yourself in the customer's shoes instead of just stating your point of view, because if only the salesperson speaks without listening to the customer to understand their needs, the sale may not happen.

· Competence: knowing the product and being able to solve problems, transmitting trust, credibility, and security.

· Posture: attitudes, actions, and treatment offered to clients. This posture expressed in terms of attitudes, is an important factor in stimulating consumer purchase intention (Mello et al., 2021).

· Sincerity: clarity, accuracy, and honesty about the product and the customer service process.

· Courtesy: friendliness, receptivity, and willingness to customer service.

· Speed: agility in service to save time for customers.

· Enthusiasm: cheerful, positive, and contagious behavior towards the client.

Besides to the aspects already presented, Mainardes et al. (2014) argue that a company that wants to excel in customer service must take strategic actions for this process, i.e., develop plans and activities that align service as a fundamental activity of the company. Therefore, service should not only be considered as an activity at the operational level, but also as an action developed at the management levels of the company (Rapert & Wren, 1998).

Regarding this guideline, Almeida (2011) states that a company can align strategic actions to customer service with the following actions:

· Knowing the customer - not limiting the registration database to basic information such as name, address, and phone number, but also maintaining a customer history (profile, purchase record and other data) that enables targeted and personalized actions for the consumer.

· Creating connections – creating mechanisms and actions to bring the customer closer and make him feel important to the company since solid bonds and relationships encourage their loyalty and improve business performance (Lima & Fernandes, 2015). Furthermore, this action can increase the company's engagement with its customers, generating affective value, loyalty and increased sales (Mello et al., 2021).

· Use of innovations – Using social networks and other communication mechanisms to disseminate news to customers based on their profile and purchase history, as consumers have a strong appetite for innovation and prefer companies that frequently offer new products and services (Nielsen, 2015).

· Strengthening the relationship – trying to win the customer over by price is a risky strategy, as he may refuse to pay higher prices. Therefore, the best alternative is to add value to the product or service by offering benefits and amenities that outperform the competitor's price and offerings (Ma et al., 2010).

· Use of social networks – a presence on social networks is essential, as it allows the company to communicate business messages and follow spontaneous comments from customers. In addition, by using videos, images, and reports, companies can increase the engagement of their audience and stimulate buying behavior (Aydin et al., 2021).

In addition to the aspects mentioned, Lewis and Mitchell (1990), confirmed by Fitzsimmons and Fitzsimmons (2010), identified five dimensions that integrate service quality and customer service as instruments of organizational competitiveness, namely:

· Reliability – delivering what it promises. Customers choose companies that deliver exactly what they were promised. The fulfilment of this expectation consists in providing a service without errors, meeting deadlines, guaranteeing the communicated price, and solving problems.

· Empathy – showing interest in the customer, demonstrating sensibility, and providing accessibility and attention through personalized service that addresses the customer's needs and proves how important they are to the company (Hoang, 2018).

· Responsiveness – willingness and commitment to respond to customer inquiries, complaints, and problems.

· Tangibility – all customer contact with the brand is considered, from the materials used in communication to the appearance of physical facilities, site hygiene, equipment, technologies, and work team. This dimension is important to strengthen the image that the customer has of the company, as it demonstrates how much the organization has invested in tangible aspects to improve the quality of attendance and services offered (Corrêa & Gianesi, 2019).

· Security – knowledge, and expertise to convey trust and confidentiality, so that the customer feels secure when doing business with the company.

From the above, it is possible to conclude that more important than making a sale is ensuring that the customer buys again, which is why strategic actions must be designed, implemented, and updated to guarantee the quality of service and its positioning as a competitive advantage in organizations.

Such aspects of customer service for competitive advantage, such as loyalty, strategic actions, and organizational competitiveness will be fundamental for the operationalization of this research.

Methodological procedures

In terms of approach, this is qualitative research that sought deeper understanding of a phenomenon of interest (Corbin & Strauss, 2015), namely customer service as a tool for competitive advantage. As for the objective, it is descriptive, as it accurately describes facts and phenomena (Triviños, 1987) related to customer service as a tool for competitiveness.

About the method, the case study was adopted to illustrate customer service and competitive advantage as phenomena of interest (Siggelkow, 2007). In addition, a single case study was adopted as it considers the study of representative and/or typical situations of the phenomenon under analysis (Yin, 2015), allowing an in-depth analysis with the expansion of existing theories and/or the creation of new or complex theories (Eisenhardt & Graebner, 2007). The chosen company and the reasons for its selection are presented at the end of the methodology section.

According to Yin (2015), it is recommended to use multiple sources for data collection when conducting case studies. Therefore, interviews, direct non-participant observation, and document analysis were used as data sources in this study. The interview, conducted on two occasions (two afternoons), was based on a semi-structured script with 36 questions, whose categories and elements of analysis, developed from the theoretical framework consulted, are presented in Table 1. A mixed grid of categories and analysis elements was used in this study, because although the analysis categories had been previously established, it was allowed to add or change categories during the analysis process (Vergara, 2015).

The interview was conducted with the company's founding partner, who works directly in defining strategies and directions for serving the business's customers. During the application of the interview, as the answers were given by the interviewee, there was the flexibility to include, exclude or redefine the order of the questions. For greater reliability, the interview was recorded (Voss et al., 2002) and after transcribed, presented to the interviewee to confirm the authenticity, or complement the information (Zanelli, 2002).

Observation as a source of evidence was done by visiting the store in two different days. During the observation, the researchers observed the behavior of consumers and employees during the customer service process. Regarding document analysis, Gil (2010) explains that documents can be written or non-written, including diaries, documents, records, correspondence, photographs, films, maps, etc.

Considering the importance of digital environments for organizations in general and for the studied company in particular, a document analysis was carried out with reports obtained in screenshots, audios and videos with customer testimonials (access to original files and voluntary posts made available on the company's website and social networks), which served to confirm the information obtained in the interview, perceptions of observations and to uncover actions that were not identified in other modalities of data collection. The testimonials are presented in the section on the presentation and analysis of the results as testimonials 1 to 6.

Data analysis followed the selection, coding, tabulation, analysis, and interpretation steps suggested by Birochi (2017) and summarized in Table 2.

Unit of analysis and reasons for selection

In this research, the object of analysis is an optics company located in Aracaju, the capital of the State of Sergipe, which has been named Óptica Alfa to preserve its corporate identity. Yin (2015) argues that when selecting a single case, the particularity of the case, its representativeness, and its potential contribution to the literature are important selection criteria. For this reason, to choose the case, was conducted preliminary research on the history of the company and its customer services, as well as observation with customer reviews on the company's website and social media (Instagram).

These procedures identified extensive reports of satisfaction and praise for Óptica Alfa's service. In addition, preliminary research identified some promotions actions that highlight the service process at this company, as the company operates a customer service program that includes offering gifts, naming eyewear models with the customer's name, points program and promotions for commemorative days such as Valentine's Day, Mother's Day, Christmas, and movie releases.

It is also noteworthy that the company, from its foundation (2018) until the first half of 2021, reached the mark of ten thousand eyeglasses sold, which demonstrates the large number of customers served by the company. In addition to the information presented, in 2020 the company was the winner of a competition in which companies from Brazil and abroad competed to participate in the Fator X Live event, described as the largest differentiation marketing event in the world. The company was also recognized by lens manufacturer Hoya as one of the most outstanding customers in Latin America in terms of good customer service.

Thus, in addition to aspects related to customer service, the company was chosen as a case study for having developed its own brand with less than three years of operation, standing out in the local market, having been the subject of journalistic articles in the Sergipe press and on national television programs; and by the expansion to other markets in the national and international context. Another fact that determined the selection of this company was the fact that it has doubled its revenues in less than a year after its constituted (between 2018 and 2019), remained on the rise, having left the digital environment for a large physical space in a prime neighborhood of the city of Aracaju.

For the reasons mentioned, it is believed that the company has particularities in customer service that make it stand out in its market and place it in a position of evidence as an object of analysis for the single case study in this paper.

Presentation and analysis of results

The presentation and analysis of the results followed the categories and elements of analysis listed in Table 1. Although it is not included in the analysis categories, during the interview, the respondent was asked about the reasons that made the customer service at Óptica Alfa an instrument of differentiation and competitive advantage, this being the first category of the analysis presented.

Customer Service as an Element of Differentiation and Competitive Advantage

To highlight service as an element of differentiation and competitive advantage, the interviewee emphasized meeting customer needs, pointing out that she strives to "understand exactly what the customer wants in order to meet the expectations they have been looking for." Based on this speech, a new question was included to check whether the company conveys consistency and credibility and meets consumer expectations, including consumers recommended by other customer. On this topic, she said the following:

A customer was recommended by a friend and after the service, she said that her friend was right: you are great, you help a lot, I really like your service and that of all the sellers. Because there are places, where one or another seller is annoying, but you all are wonderful.

As for meeting customer expectations, the interviewee then affirmed: “I believe so, that there is conformity. Even because there is no universal standard for customers, there is a standard of service [...] it is very much what we are, that is, it is not fake”.

In addition, the interviewee was asked what she believed to be the company's differential, to which she replied:

Creativity, marketing campaigns that involve the customer differently, always looking for approximation, even in an informal way, being open to assisting, letting the customer feel free to approach, organizational climate for the customer to want to be part of Óptica Alfa [...] we are a new concept of optics, the same price for all eyeglasses so that the customer can buy what he liked best, we put ourselves in the customer's shoes so that he does not have to choose eyeglasses for the price, [and] to prevent the customer from liking one and having to opt for another that he can afford.

Since the interviewee defined her company as a new concept of optics, the reasons for this classification were asked, to which the interviewer replied:

It is common for customers to arrive at Óptica Alfa traumatized by the fact that they bought from another optical company and only later realize that they did not need that type of lens or without understanding why they bought one product over the other. Usually, only one type of lens is presented as if there was only one option that meets the customer's health needs without giving other options with different prices for the customer to choose from, but there is not just one option, there are several and the customer needs to know.

As an example, she continued:

I could say that these [competing] optics are the kind that consider the lay customer, and indeed they are when it comes to lenses. That's why our service makes a point of explaining and being transparent, so that the customer knows what lens they are using, knows exactly what they are paying for, and knows what they are buying. Even if they need to replace the lens, they will know the thickness of your lens and anti-reflective coating, and if they need to change it, they will understand why. We strive for transparency in communication, to share information that was not available to the customer for many years.

In this context, the interviewee mentioned the reasons that make customers choose her company, that is, what would be her differential and competitive advantage, she commented:

For the relationship and approach to the customer through Instagram which shows the values and explaining how the service works in the company, which in large part comes down to making it clear that the customer knows what he is buying at Óptica Alfa. It's clear to me that many buy because of the relationship they build with the team.

From this speech, the interviewee has detailed how service is a tool of differentiation and competitive advantage in her company, she explained: "To bring the customer to the store, the relationship begins on social networks in an online pre-service, where communication, is not only clear, but also is light and informal, to be closer".

She also stressed the importance of service, after attracting the customer to the store, and after-sales.

Our service starts in the social networks and with the presented content, explaining details of the eyeglass, lenses, sunglasses, the eyeglasses frame model and corresponding face types, among other explanations that are relevant information, [so] the customer arrives in the store to complete the purchase, and the information that is normally offered in face-to-face service has already been shared through the online social network.

In a document analysis with the screenshot of a comment on Instagram of the company, it was possible to verify the reliability transmitted by the organization, in which one of the customers said:

I loved the explanation about the lenses in the preliminary service and was one of the points that made me a customer. I have been wearing eyeglasses for fourteen years and never knew what lenses I was using; it was practically just a matter of choosing the eyeglasses frame (Testimony 1).

This finding fits into the reliability dimension (Fitzsimmons & Fitzsimmons, 2010), in which customers choose to do business and relate to companies that accurately deliver what they were promised.

It was also noticed, according to the messages provided by the interviewee, that the explanation about the types of lenses and all aspects of the products sold is not limited to the company's posts on Instagram, but also involves private messages, in response to customers and yours doubts, budget requests, to provide enlightening and detailed service, even before the first contact in the physical store.

Considering that the service in this company is based on explaining and sharing technical aspects of the marketed product, it can be stated that this venture establishes the service based on useful factors (rational factors, use at work, study or activities of needs (Redda, 2020) as a means of delivering the right product to the customer, ensuring his satisfaction and increasing the chances of returning for new purchases.

Moreover, this strategy of using clear communication mechanisms optimizes the buying process and builds a relationship that promotes convenience and speed for the customer (Adebayo, 2021) and loyalty for the company (Hong et al., 2019).

This strategy of using clear communication mechanisms results in better customer service, in addition to making their purchases easier and faster (Adebayo, 2021), fosters rapprochement with the company, and establishing a relationship that promotes practicality, speed, and loyalty (Hong et al., 2019).

The categories and elements that emerged from the interviewee speeches about customer service as an element of differentiation and competitive advantage at Óptica Alfa are listed in Table 3.

By implementing differentiation mechanisms, such as setting the same price for all eyeglasses and pre-service on social networks, the respondent demonstrates the implementation of actions and strategies to distinguish their company in the market and differentiate it from competitors (Rosa & Deluca, 2015).

Customer loyalty tools

Considering that loyalty based on customer service is one of the mechanisms for competitive advantage (Hassan & Rehman, 2016), we sought to identify the elements of empathy, humanization, competence, posture, sincerity, courtesy, speed, and enthusiasm (Ribeiro, 2007) in the Óptica Alfa’s customer service.

Regarding the aspects of the empathy element, the interviewee said that:

The team is always looking to listen to the customer, put themselves in their shoes, be willing to solve problems that go beyond the company's obligation to offer support and understand how the customer feels. It's about identifying our customers' needs, putting ourselves in their shoes, and not just closing a sale.

And she added:

[The attendants] always try to explain and clarify that it is not always necessary to make the lens recommended by the ophthalmologist and show the different options that meet the needs of the customer at an affordable price. [...] And we always serve in a consultative way, trying to help and explain the reason for each product.

The speeches obtained corroborate the perception that empathy is not just about offering understanding to consumer needs, but showing interest, sharing and attentive care with customers, making them feel like “guests of honor” during service (Hoang, 2018). To do this, as in the case analyzed managers should hire employees who can sense customers' expectations and perceive and respond to consumers' thoughts, feelings, and intentions in order to create a positive opinion about the brand during the interaction between the salesperson and the customer (Bahadur et al., 2018).

Regarding the element of humanization, the respondent reported that:

We always call our customers by name. As soon as the customer arrives at the store, we ask them their name, except for some whose names we already know, to serve the customer in a more personal and individual way. We call the person by name and not boy or girl because that can sound derogatory and false. There are people we call by their personal nickname or an abbreviation of their name, it depends on the type of customer. It is important to call the person by name so that the person understands that you are paying attention to them.

The interviewee's understanding underlines the importance of humanization in service and emphasizes that the customer appreciates being treated exclusively, if only by being addressed by his name, which shows his uniqueness and importance to the company (Dantas, 2010).

In order to identify the relevance of the element of competence, it was asked whether Óptica Alfa's employees convey trust and credibility to customers because they have sufficient knowledge about the products offered. The respondent said:

Absolutely. Knowledge conveys certainty to the listener. If the person is not sure about the information about the product, the customer cannot be sure that he will get what he needs. Here at Óptica Alfa, our sellers are prepared, trained and always up to date. The attendant knows what he is selling, knows all the features of our product very well and conveys to the customer that he is making the right purchase.

When talking about the posture in attendance, the interviewee told that:

The store has the face of the owner! We communicate the values of the company in meetings, training and hiring, showing how it should be, and the team learns. We explain the company's values and how those values shape our decisions, and we make it clear what is a priority in the company's operations and in our customer service.

These findings corroborate the perception that managers need to provide training in product knowledge so that employees have the necessary competence, which, in addition to maximizing customer satisfaction, is a preventive measure against damage (consumer dissatisfaction) to the brand (Lee et al., 2020).

In addition, the interviewee said that:

I work with a decentralized customer service. In the past, customers were served by me, so of course they look for me, but I have started to delegate this service to the team and increase communication on Instagram to show the team and create identification with customers.

It is worth noting that the respondent recognizes that she is an example of service and preference for her customers. For this reason, she presents her sales team not only in face-to-face service, but also in other communication channels of the company, which strengthens the bond with consumers, facilitates the process of customer identification and allows the manager to dedicate herself to activities and strategies that develop and optimize her management practices and customer service. In this way, it does not create dependence on one or the other seller but makes them equally attractive to consumers.

The interviewee also explained that "the customer can have greater identification with an attendant because each has its own personality. But as far as the treatment, the explanation of the details of the eyeglasses and the purchase, the service is always the same".

Complementing the arguments about customer service expressed by the standardization in this process, the analysis of the document Sales Procedure of Óptica Alfa found that this process follows the following steps: Receiving and introducing the customer; Identifying the type of purchase; Verifying the interest in eyeglasses with or without corrective lenses; Analyzing the customer's taste; Finding out if the customer has come through an indication; Explaining the loyalty model; Explaining the score; Registering the customer; Registering the purchase; Payment; Packing the product; Thanking the customer for the purchase, sending a WhatsApp message.

This understanding is confirmed by Tarziev et al. (2018), who report that the development and implementation of standards requires that the organization accurately identify the types of customer service, the costs of providing alternative services, and the measures to measure and control the services provided. These authors affirm, as reported by the interviewee, that even in the face of the existence of service standards, it is necessary to know the demand and requirements of each consumer, and thus adapt the service to their needs and behavior.

The actions taken in this company to implement an appropriate attitude toward service are the result of a shared sense of organizational values, human resource management initiatives (rewards and training), ownership (management), and responsibility (employee discipline) (Boateng et al., 2022).

The interviewee reported other aspects that she considers important to retain the buyer and have a competitive advantage in customer service. On this topic, she noted that service is a continuous process that begins before the purchase. She said that:

In addition to the pre - service, we work with sending messages thanking the customer for the purchase when they leave the store; a birthday message, a month after the purchase, to find out if the customer has gotten used to the eyeglasses and also a more personal email, not robotic, with a message related to the feelings of that moment.

The analysis of the screenshots and comments on Instagram of the company confirms the statement of this interviewee, in which it is common to find testimonials in which customers thank the sellers for their attention; for send messages on different dates, asking about satisfaction with the purchase, if the company can be useful or simply reminding of the consumers. The messages sent have a personal character, calling the customer by name and mentioning his specific purchase, without using standardized texts.

This practice of Óptica Alfa testifies to a careful and individualized attention to customers, even after the purchase. On this topic, Coelho and Henseler (2012) emphasize that personalization increases perceived service, consumer satisfaction, trust, and customer loyalty to a service provider.

The case analysis also reveals that virtual customer service, whether pre-purchase or post-purchase, is a tool for business differentiation and that customer interaction in virtual environments, as occurs in logistics services in China, has a positive impact on consumers' purchase and repurchase intentions (Yang, 2017).

Considering the sincerity element, the audio documentary analysis sent by a customer reinforces the company's attitude:

I was at Óptica Alfa and [name of salesperson] informed us that she was serving a wholesale customer and that she would not be able to give us attention at that time. So, I said not to worry and that she didn't need to pay attention to me, that I just wanted to look at the eyeglasses to choose. So, she was very polite, let us in and we chose. I just wanted to say that you [owner] and the girls [salespeople] make all the difference, the service makes all the difference in the experience we have at the store, it's not just buying eyeglasses, it's feeling welcomed in the place. [...] You are sensational (Testimony 2).

By being sincere and even taking a little longer to begin service, the salesperson was able to close the sale with customer satisfaction. This is because customers prefer sincere responses, even if negative, to positive responses that represent untruths and/or fail to materialize, so sincerity leads to higher levels of repurchase intention and satisfaction (Ma & Wang, 2021).

Concerning the courtesy element, when asked about the effort to please the customer, the interviewee stated that:

We are very receptive because I think it's bad when someone to enter the store and not receive attention. So, whenever a customer enters, even if the store is full, we talk to each one individually to receive, pay attention and tell them to feel free to call us.

This interviewee's report was confirmed in one of the observations, in which it was noticed that even when all the saleswomen were busy, customers who arrived at the store were welcomed, invited to make themselves comfortable, and informed that they would soon be served.

Costa et. al. (2015) reinforce this understanding by explaining that customers look for companies that treat them with courtesy, attentive employees, and a pleasant and receptive environment where they feel comfortable. Thus, the company under study conveys credibility to its customers by making courtesy a fundamental aspect of its service, which leads them to be loyal to the company (Gopi & Samat, 2020).

As for the speed element, questions were asked about agility and readiness to serve the customer, and the interviewee said that the service "happens in a satisfactory time and we never receive complaints about the service time". The interviewee mentioned the day on which the observation was made, saying:

Of course, it can happen, as happened today, that the store was very crowded and the customer had to wait a while, but it's just a matter of how you talk to him, ask him to be patient and everything works out. [...] And it is very difficult for a customer to wait in the store [...] And we also do not accumulate many messages on WhatsApp and Direct [from Instagram].

To confirm the respondent's statement, during the afternoon that we spent observing in the store, an intense movement was noted between noon and 1:00 pm, the time when only one employee was working, and even then, all customers were served, and four sales were completed. In addition, it was found that the infrastructure of the store facilitates customer service, as the large and well-lit space with well-positioned eyeglasses facilitates communication with customers, and salespeople can respond quickly and flexibly to buyers’ expectations and requirements.

As far as enthusiasm is concerned, the interviewee made it clear that in order to hire an employee, she requires that the employee be a happy person:

Joy is an identity of Óptica Alfa. It is humanly impossible to be well all the time, but we try to serve the customer with a smile and good mood. I think that is already part of our identity and makes the difference in the relationship with the customer.

By instituting enthusiasm as a requirement for hiring new employees, the interviewee demonstrates, as was identified in Tainan (Taiwan), that customer service must demonstrate the passion of employees and make customers perceive enthusiasm, the profession and the efficiency of an organizational team, since these elements make positive contributions to improving the company's image and revenue (Huang, 2016).

The elements and actions for customer loyalty, identified in the interviews and other forms of data collection are summarized in Table 4.

The findings of this category of analysis underline the importance that Óptica Alfa attaches to the customer since different aspects and requirements are simultaneously applied in the customer service process, demonstrating that simplistic practices or only replicated from other companies do not guarantee quality in service.

Strategic actions for customer service

For this category of analysis, the interview was conducted to identify the elements of knowing the customers, making connections, using innovations, strengthening relationships, and using social networks. For the element of knowing the customer, the interviewee said that:

To provide good service, you have to surprise the customer, like on Customer Day, when we gave every customer a personalized cell phone case with their name on it, or on Black Friday, when we gave eyeglasses to those who were already customers.

And continued:

Or when we send selected customers a personalized gift that has nothing to do with eyeglasses but shows that the company knows the customer and chooses the gift according to his taste and personality, observing the person's preferences.

Based on this speech, a new question was asked during the interview to find out how the company perceives these characteristics and consumer preferences, and the interviewee said:

We follow and observe customers during service, literally listening to what they have to say and making sure we understand them. We even follow some customers on social networks to get to know their preferences better, and we use this information in our campaigns to surprise them.

It is worth noting that Óptica Alfa, in order to get to know its customers better, has launched a weekly program, the "Alpha Squad Analyzes", which monitors the profile of registered followers and displays the eyewear models that best fit the person. With this strategy, the company has managed to get closer to customers and convey reliability, besides explains product details, and creates a sense of importance among consumers.

This is a relevant perception of the paper, because the interviewee shows that the study and observation of customers goes beyond the perception of the products sold and also includes the tastes, preferences and personality traits of the consumer, which generates satisfaction and puts the brand in evidence. In addition, when looking for mechanisms to get to know the customer beyond their purchase expectations, the company better knows its consumers and their needs, serves them better, makes the relationship closer and lasting (Unes et al., 2019), and uses this knowledge about their preferences to offer products and customize services that increase their perception of value (Bonaretti et al., 2020).

Regarding the element of creating connections with the customer, the documentary analysis of a screenshot reported how the company constitutes this connection with consumers. In the screenshot, a costumer said:

I became a follower of yours a while ago, you didn't even have your own brand yet, but since then I've never had the opportunity to buy my “Alpha eyewear”. [...] I want to record my admiration and gratitude; I am very satisfied with my first eyeglasses. I love the way you treat customers, how the company creates an affective and respectful bond, how it provides satisfaction, pampers and even prices” (Testimony 3).

Furthermore, the interviewee was asked how the company demonstrates the importance of creating connections with the customer, to which she replied:

The way to demonstrate that the customer is important is to tell them that. So much so that in the campaigns we carry out we always talk a lot about this matter of thanking you for having you with us, we also thank you at the time of purchase, we have the loyalty club that gifts the customer with eyeglasses as a form of thanks, which is still a way to demonstrate they are important [...] on some dates we always see a way to say thank you. For example, on the customer's last day, we sent a message to each customer thanking them for their loyalty, especially during the pandemic, which was a difficult time. I think that shows the importance is a lot of the relationship we seek to maintain and the dialogue with the customer. Anyway, everything we do, whether it’s a message, e-mail, campaign, shows how special they are and is a way to strengthen bonds.

This interviewee's speech was also corroborated in the documentary analysis of a video in which a customer said the following:

I have heard a lot about Óptica Alfa, especially here on Instagram, and since I have heard so much about it, I have to confess that I thought it was just marketing. I always heard about it, but I did not follow it because I really thought it was this kind of company that talks a lot and does little. [...] Until Óptica Alfa launched a Mother's Day campaign, I entered the contest with a sentence about my mother and got involved with the brand even before I became a customer. Time passed and I wanted to change my eyeglasses, the model of my old ones did not fit me anymore, besides I needed a new lens, I decided to buy a new pair of eyeglasses and chose Óptica Alfa. The service via WhatsApp, all the care they take and the great interest in explaining and making us understand the importance of each type of lens, makes us feel that we can choose a lens even without treatment, but also makes us understand the cost-benefit ratio of each lens. [...] To conclude with a golden key, at the end of the purchase, the salesman asked me if I wanted my name on this model of eyeglasses, and from that day on, the model I bought was mentioned on the company's website with my name (statement 4).

On the issue of captivating the customer and strengthening relationships, on the result that the company has achieved from this effort to add value to its offer, the interviewee said that:

Thank God our company has grown a lot, our customers have also increased, most of them through referrals, and that means everything is going well because the best thing is that if you like something, you recommend it, and most of our clients are referrals.

The importance of creating connections to gain customer loyalty is also confirmed by Monteiro (2016), who makes it clear that loyal consumers recommend the company to other people. However, customer loyalty is not bought, but conquered by the company’s attitude, making efforts to captivate, respect, and covey trust.

The elements of using innovations and social networks complement each other. For this reason, they were analyzed together during the interview to deepen the perception of their implementation in the company. About these elements, the interviewee said:

For example, when we launched our premium collection, we generated customer expectation through Instagram and shared it (premium collection) first-hand with current customers [...] Through the registered email, customers received a secret link that led to the website where the models were available for purchase. Since it was a pre-sale, only loyal customers who had received this secret link had access. Then, when we opened to the public, many of the models were no longer available.

Actions like these of Óptica Alfa are considered ideal by Almeida (2011). He argues that it is important to use all the company's news to engage with customers in a targeted way, taking into account their interests and profile identified through their purchase history.

Regarding the use of social networks, the interviewee says that:

I see social media as a gateway for customers. That's where the customer gets to know Óptica Alfa, and values like transparency and trust have to be communicated there first. At least that's how we do it.

When asked about the relevance of using social networks as a strategy for attracting and retaining customers and gaining a competitive advantage in customer service, the respondent replied that:

It is certainly a form of attraction and loyalty. We use social media in a variety of ways. Most of Óptica alfa's customers come through social media. It's natural to know the company from someone who has talked about it. Then they go to the social network to get information, and after that it comes to the store, where the customer can be sure that the company is what it broadcasts.

The interviewee's speech underlines that, although the company's Instagram is responsible for attracting a significant portion of customers, the congruence between the communication transmitted and the reality found at the time of service is a decisive factor in the loyalty of the customer, who sees his expectations fulfilled and remains satisfied.

In this sense, the case confirms that the use of innovation (launch of new models) combined with technological tools (social networks), as found in Indian companies, is essential for retail companies to operate effectively and efficiently (Mukthar et al., 2022). In addition, it is worth noting that the importance given to social networks in this company shows that this organization is in line with today's digital age and that the use of technology-based strategies is not only of great importance in gaining sustainable competitive advantage, but also has a direct impact on customer service and digital capability building (Li et al., 2022).

The interviewee's statements on the previous two elements open up space for discussion on strengthening the relationship with the customer, as the company seeks to delight the customer through exclusivity, among other strategies. On this topic, she said the following:

Whenever we launch something new, we first think about how to surprise our current customer. Sometimes we send personalized, simple, and meaningful gifts. Often not strategically, but spontaneously, with reciprocity.

Although it is considered something natural by the respondent, Santos et al. al. (2019) affirm that the company must constantly analyze the requirements to captivate its customers, strengthen relationships and win their loyalty, otherwise there is a risk of losing them. Regarding this element, in the documentary analysis, in a video posted on the company's Instagram profile, a customer reported the reasons that led her to choose Óptica Alfa to buy eyeglasses for a special occasion:

I looked for Óptica Alfa because I knew they would be able to meet my needs. It is a company that understands [your customers], that provides much more than eyewear. I remembered you because I know you like to be present at important moments in the client's life (Testimony 5).

Óptica Alfa's effort to captivate the customer and strengthen the relationship increases the perception of the company's value and leads to consumer loyalty. This confirms the finding of the Performance Research Associates report (2011) that in order to maintain a consistent business relationship, it is necessary to provide a positive and memorable experience, in other words, to strive to surprise and captivate the customer in a unique way.

It is worth noting that while the interviewee highlighted exclusivity as an element of strengthening the relationship with customers, it is clear that this element is a consequence of previous actions involving consumer profile analysis and comprehensive support for personal and virtual customer services. In this case, the relationship with the customer is the result of the integration of people (employees), processes (mechanisms and forms of service), and technology (digital means of communication), which make it possible to understand the customer through what consumers themselves say, which increases the company's assertiveness with consumers, fosters their loyalty, and provides profitability (Lokesh et al., 2022).

Table 5 shows the main findings of this category of analysis.

In general, the results obtained in this category of analysis extend the perceptions of Ibojo and Asabi (2015), who strongly suggest that actions aimed at service make customers loyal and increase their frequency and regularity of purchases. Moreover, the strategic actions not only enable the satisfaction of existing customers, but also promote the conquest of new consumers, as customers themselves become multipliers of the brand by spontaneously announcing their satisfaction in their personal and virtual spheres of influence.

Customer service as a tool for organizational competitiveness

This section analyzes the evidence on the elements of reliability, empathy, responsiveness, tangibility, and security.

As for reliability, the interviewee reported that: “In customer service, we seek to deliver the promised service, it is an obligation”. In addition, she said that employees must “show confidence when dealing with customer problems”. Complementing this set of aspects, the interviewee explained that during the service, the company seeks to “deliver the right services the first time the customer seeks service” and this involves the delivery of products within the established deadline, as “we usually give an extra deadline and we always deliver before”, in addition to “we keep records of errors in the customer service to prevent them from being repeated and to facilitate the next services”.

It should be noted that the element of reliability results from other actions implemented in the organization, such as strategies to get to know the customer, the use of social networks and even the communication mechanisms used by the company, which show that the service offered is the result of a series of planned actions and not simply a random and/or improvised action. Proof of this is that the company records all errors in the service process, tries to correct them with its employees and, when necessary, updates the document Óptica Alfa Sales Procedure (Company Service Manual). It is understood that the reliability conveyed by Óptica Alfa promotes sales, strengthens consumer confidence, increases the perception of quality, reduces the risk perceived by customers and improves the company's reputation in the market.

Regarding the aspect of empathy, the interviewee highlighted that the company strives to given "individual treatment to customers, treat them with attention, know their interests, understand their needs and offer convenient service times."

She further said that:

We always want to sell more, of course, but profit is not the main factor, in the sense that we do not try to push the product and push the customer to buy it in order to achieve the goal. For example, if [the customer] has doubts, we advise them to think, go home, and come back the next day.

During the observation, it became clear that although Óptica Alfa uses very strong marketing strategies, empathy is widely practiced in the organization, especially due to the way the salespeople perform the service, simultaneously seeking to satisfy the needs of the customer and understand his behavior, humor, expectations and requirements at the time of purchase.

In this context, as observed in Óptica Alfa, Wieseke et al. (2012) emphasize that the empathy of the employees induces a friendly behavior in the customer, making him feel welcome and respected. For this reason, these authors also underscore the need for a selection process that recognizes empathic candidates, as well as the implementation of training that arouses these behaviors in employees, as was found in the company's study.

In highlighting aspects of responsiveness in service, the interviewee emphasised elements such as "information and quick service, willingness and understanding to help the customer." She also said, "We strive to inform the customer when the services will be provided [...] we provide quick service, always show willingness and are ready to respond to requests."

This report reminds of KPMG International Research's (2020) view that companies need to keep their customers fully informed about the resolution of problems and the dates when products and services will be received and continued in the present and future. In addition, responsiveness in the analyzed case shows the availability of the company to the consumer, not only providing guarantees and deadlines to the customer, but also proving the existence of management processes and measures that guarantee the quality, responsibility and reliability of the service offered (Hoang, 2018).

As for tangibility, the interviewee stated that the company uses "modern equipment, facilities with attractive colors, products placed in points that attract customer’s attention and facilitate the access by employees". During the observation, it was also noted that the physical space of the store is used as a means of dissemination since the actions and campaigns of the company are highlighted. On this subject, the interviewee added:

We always try to maintain a physical structure that reminds us who we really are [...] in everything we are different, from the arrangement and organization of the physical space, Óptica Alfa is different from other optics. And everything influences the customer's view of the company. The store clearly shows how we want to be: lighter, younger, more modern, more intimate, so that the customer feels more comfortable.

Thus, it can be seen that in Óptica Alfa, similar to what was found by Silva et al., (2020), aspects of the environment and spatial arrangement such as the arrangement of the furniture, the eyeglasses, the position of the saleswomen, the lighting, the colors, and the background music have an influence on the purchase decision, mainly because are factors that activate consumer preference and motivate him to buy the visible products. Similar to the Lithuanian companies, offering goods and services associated with physical and image factors (tangibility), as in the studied case, is a factor that activates consumer preference (Černikovaitė et al., 2021) and gives the company a competitive advantage (Jerônimo & Medereiros, 2014).

Finally, regarding the element of safety, the interviewee said that employees inspire confidence because "they have the necessary knowledge to serve the customer and are consistently cordial [...] it is very difficult the employee is not well at the time of service.

In a documentary analysis of a comment posted on Instagram of the company, new aspects related to the security transmitted by the service were revealed, in particular the online service in which one of the customers wrote:

Even being attended by Direct I felt very safe, I sat down with my husband, and we discussed, now like knowledgeable people, the best lenses for us. And all thanks to the explanations we received. What I did not understand, I asked and promptly got an answer (Testimony 6).

The interviewee's statements and the testimony presented corroborate that the seller needs to attest to his trust and know the product or service in detail when he serves the customer. He must also know how to present the benefits and answer any questions about the product, payment method, and delivery terms (Sangtani & Murshed, 2017). For this reason, service providers should invest in training that improves employees' ability to build trust and consistently deliver excellence to maximize customers' perceptions of service quality (Bourdin & Sichtmann, 2022).

The summary of the most important findings on the relationship with the customer as a instrument of competitiveness is shown in Table 6.

This category of analysis shows that customer service is a competitive advantage when it results from a process of planning and organizational action that encompasses the entire structure of the company, including physical equipment, employee attitudes, organizational values, and managerial goals, that is, the isolated action of customer service at the time of sale does not constitute an advantage or strategic differentiator, but the process of customer service and management support of this activity qualify it as a competitive advantage, as is the case with Alfa Optics.

Furthermore, the analysis of Óptica Alfa corroborates the findings of Mutua (2020), that the company that wants to stand out from the competitors must develop strategies that differentiate it, especially about service, since customers are demanding and to attract them, it is necessary that the service offers innovation and employee commitment, going beyond predictable and routine practices (Mahmoud et al., 2017).

Final considerations

Customer service has proven to be a basic requirement for the success of companies, especially due to the strong competition and the improvement of the quality of products offered in the market. In this context, this study sought to analyze customer service as an element of competitive advantage in a retail company in the optical industry.

The results show that the competitive advantage derived from customer service is the result of several factors. Among them, product knowledge is an essential skill for the salesperson, as it enables him or her to present the benefits and features of the items sold in a technical, precise, enthusiastic, and persuasive manner, thus attracting and convincing customers.

In addition, the company should not only seek the customer to sell and/or offer products, but also establish informal communication to find out if the customer is doing well and offer help in aspects that are not directly related to the products sold. In this way, the company builds a bond with its customers, gets to know intimate aspects of their personality, and becomes the preferred supplier in the moments of purchase.

Another lesson from the case studied is that companies should not only be concerned with the quality of their products, since customer service is also a key element in consumer satisfaction, company differentiation and building competitive advantage. After all, strategies based solely on product quality can away consumers or discourage them from returning for new purchases.

An important finding of the study is that the company follows its customers on social networks and thus learns about their preferences, behavior, and leisure and consumption habits. This allows it to develop specific actions for its consumers and improve customer service techniques to satisfy them in addition to offering optical products. This behavior shows that social networks should be used not only to promote products and brands, but also to find out what customers want to buy and how they want to be served.

Still in this prism of reflection, the use of social networks, as in the company under study, is a powerful tool to attract customers, establish contacts and arouse their curiosity. However, it is not enough to just arouse consumers' attention, it is necessary to transfer the practices demonstrated in digital media to face-to-face service and guarantee products, services and relationships at the level desired by the customer.

This business strategy deserves to be understood and reinforced by other organizations because access to social networks is free or low cost; companies can collect customer data, serve them excellently, and expand their product portfolio and service practices without having to hire consultants or specialized research.

Thus, the results prove that customer service is a competitive advantage and a source of cost reduction for companies because organizations that excel in this process, like Óptica Alfa, can promote their products for free or at low cost, making their customers the main promoters of the brand.

Based on the obtained results, it is recommended to deepen the discussions on the role of social networks in building a competitive advantage based on customer services. In addition, it should be investigated whether the competitive advantage resulting from the customer service is equally important for service providers, trade, and industry, and whether the characteristics of the customers (men, women, elderly, education, income, etc.) influence the competitive advantage resulting from the service.

In general, companies that aim to make customer service a competitive advantage must develop an integrated and simultaneous process based on the customer's needs and the firm's plans. In this process, service must be based on customer loyalty measures, strategies aimed at customer service, and customer service as a tool for competitiveness, i.e., although price, location, quality, and payment methods are important attributes, it is service and the customer relationship that make optical companies stand out in the market (ssOtica, 2022).

Moreover, in order to gain a competitive advantage, it is not appropriate to adopt universal and rigid customer service standards, but rather to establish general procedures that reflect the company's values and can be adapted to the different groups and buyers’ profiles. It is this integration between technology (social networks), standardization, customization and organizational values that positions customer service as a tool of competitive advantage.

Furthermore, customer service cannot be sustained as a competitive advantage if it is based on lies and misleading advertising, because dishonest service may result in a sale, but causes dissatisfaction (later), discourages repeat purchases, and hinders buyer loyalty.

The main theoretical contribution of this research is the validation of the categories of analysis and the identification of the aspects that compose the elements studied, offering additional discussions on the characteristics of each of them. From a practical point of view, this study illustrates and discusses elements and practices that can be applied in different companies that want to make customer service a tool of differentiation and competitive advantage.

It is concluded, then, that customer service has a real potential to differentiate the company in the market and be a competitive advantage for organizations. However, this advantage is the result of a broad process of consumer study, management discussion, integration between corporate strategies, adequacy of the physical structure, training of employees, acting in social networks and strategic planning that together support - and receive inputs - to enhance the role and benefits arising from customer service, that is, this service is not just an operational procedure performed by attendants and salespeople, but a corporate strategy that is reflected in differentials and competitive advantages for the business.

References

Abióptica - Associação Brasileira da Indústria Óptica. (2022). Setor de lentes e óculos se reaquece em 2021. https://www.abioptica.com.br/setor-de-lentes-e-oculos-se-reaquece-em-2021/

Abióptica - Associação Brasileira da Indústria Óptica. (2019). Setor óptico cresce 3,7% no primeiro trimestre de 2019. https://www.abioptica.com.br/setor-optico-cresce-37-no-primeiro-trimestre-de2019/.

Adebayo, A. A. (2021). Impact of Communication on Customers’ Satisfaction in Hospitality Industry in Kwara State, Nigeria. African Scholar Publications & Research International, 20(7), 76-93. https://bityli.com/mGNAG

Almeida, C. (2011). 5 Estratégias para fidelizar os clientes. https://exame.com/pme/5-estrategias-para-fidelizar-os-clientes/.

Angelova, B., & Zekiri, J. (2011). Measuring Customer Satisfaction with Service Quality Using American Customer Satisfaction Model (ACSI Model). International Journal of Academic Research in Business and Social Sciences, 1(3), 232-258. https://bityli.com/AqXlr

Aydin, G., Uray, N., & Silahtaroglu, G. (2021). How to Engage Consumers through Effective Social Media Use—Guidelines for Consumer Goods Companies from an Emerging Market. Journal of Theoretical and Applied Electronic Commerce Research, 16, 768–790. https://doi.org/10.3390/jtaer16040044.

Azigwe, J., Maryir, G., Asunka, B., & Manamzor, F. (2016). Customer satisfaction for company growth: the roles, responsibilities, and skills required of the sales force in Ghana. British Journal of Marketing Studies, 4(5), 74–88. https://bityli.com/jmLYD

Bahadur, W., Aziz, S., & Zulfiqar, S. (2018). Effect of employee empathy on customer satisfaction and loyalty during employee-customer interactions: The mediating role of customer affective commitment and perceived service quality. Cogent Business & Management, 5(1). https://doi.org/10.1080/23311975.2018.1491780

Bengtsson, S., Hertzberg, J., & Rask, I. (2020). The Relationship Between Service Quality, Customer Satisfaction and Brand Loyalty - A Study Comparing Generation X and Y in Sweden. [Bachelor Thesis, Jönköping University]. https://www.diva-portal.org/smash/get/diva2:1437946/FULLTEXT01.pdf

Birochi, R. (2017). Metodologia de estudo e de pesquisa em administração. Departamento de Ciências da Administração / UFSC. https://bityli.com/PRqcs

Boateng, H., Amenuvor, F. E., Adam, D. R., Agbemabiese, G. C., & Hinson, R. E. (2022). Exploring customer stewardship behaviors in service firms. European Business Review, 34(4), 541–555. https://doi.org/10.1108/ebr-09-2021-0203

Bonaretti, D., Bartosiak, M., Lui, T.-W., Piccoli, G., & Marchesani, D. (2020). “What can I(S) do for you?”: How technology enables service providers to elicit customers’ preferences and deliver personalized service. Information & Management, 57(6), 103346. https://doi.org/10.1016/j.im.2020.103346

Bourdin, D., Sichtmann, C. (2022). First Impressions of Foreign-Born Frontline Employees: Impact on Customer Participation: An Abstract. In: Pantoja, F., Wu, S. (eds) From Micro to Macro: Dealing with Uncertainties in the Global Marketplace. AMSAC 2020. Developments in Marketing Science: Proceedings of the Academy of Marketing Science. Springer, Cham. https://doi-org.ez22.periodicos.capes.gov.br/10.1007/978-3-030-89883-0_162

Černikovaitė, M., Karazijienė, Ž., Bivainienė, L., & Dambrava, V. (2021). Assessing customer preferences for shopping centers: Effects of functional and communication factors. Sustainability, 13(6), 3254. https://doi.org/10.3390/su13063254

Chandra, C. & Kumar, S. (2000). Supply Chain Management in Theory and Practice: A Passing Fad or a Fundamental Change? Industrial Management & Data Systems, 100, 100-114. http://dx.doi.org/10.1108/02635570010286168

Coelho, P. S., & Henseler, J. (2012). Creating customer loyalty through service customization. European Journal of Marketing, 46(3/4), 331–356. https://doi.org/10.1108/03090561211202503

Conceição, J. A., Silva, L. A. da, & Silva, T. S. (2021). A percepção pelo cliente quanto à qualidade no atendimento em empresas varejistas num centro de compras em Imperatriz - MA. Humanidades & Inovação, 8(49), 125–140. https://revista.unitins.br/index.php/humanidadeseinovacao/article/view/4968

Copeland, M. K., & Mahsud, R. (2020). Exemplary Customer Service: Strategies for Establishing a Competitive Advantage and Improved Financial Outcomes. Graziadio Business Review, 23(2). https://gbr.pepperdine.edu/2020/09/exemplary-customer-service/

Corbin, J., & Strauss, A. (2015). Basics of Qualitative Research. Thousand Oaks, CA: Sage.

Corrêa, H. L., & Gianesi, I. G. N. (2019). Administração estratégica de serviços: operações para experiência e satisfação do cliente. São Paulo: Atlas.

Costa, A. de S. C., Santana, L. C. De, & Trigo, A. C. (2015). Qualidade do atendimento ao cliente: um grande diferencial competitivo para as organizações. Revista de Iniciação Científica – RIC, 2(2), 49-69. https://cairu.br/riccairu/pdf/artigos/2/10_QUALIDADE_ATEND_CLIENTE.pdf

Dantas, E. B. (2010). Atendimento ao público nas organizações: quando o marketing de serviços mostra a cara / 3. ed. – Brasília: Editora Senac DF.

Darmawan, D., Mardikaningsih, R., & Hadi, S. (2017). The Effect of Service Quality, Customer Satisfaction and Corporate Image on Customer Loyalty in the banking sector in Indonesia. Journal of Business and Management, 19(11), 46-51. https://doi.org/10.9790/487X-1911064651

Desfitrina, D., Zulfadhli, Z., & Widarti, W. (2019). Good service strategies affect competitive advantage. International Review of Management and Marketing, 9(6), 135–144. https://doi.org/10.32479/irmm.8853

Detzel, D. H., & Desatnick, R. L. Gerenciar bem é manter o cliente. São Paulo: Pioneira, 1995.

Donaldson, W. G. (1995). Manufacturers need to show greater commitment to customer service. Industrial Marketing Management 24:5, 421-430. https://doi.org/10.1016/0019-8501(95)00032-6

Eisenhardt, K. M., & Graebner, M. E. (2007). Theory building from cases: Opportunities and challenges. Academy of Management Journal, 50(1), 25–32. https://doi.org/10.5465/AMJ.2007.24160888

Fitzsimmons, J., & Fitzsimmons, M. (2010). Administração de serviços: operações, estratégia e tecnologia de informação. 2 ed. Porto Alegre: Bookman.

Gil, A. C. (2010). Como elaborar projetos de pesquisa. 5. ed. São Paulo: Atlas.

Gopi, B., & Samat, N. (2020). The influence of food trucks’ service quality on customer satisfaction and its impact toward customer loyalty. British Food Journal (Croydon, England), 122(10), 3213–3226. https://doi.org/10.1108/bfj-02-2020-0110

Hassan, S. M. U. &, Rehman, C. A. (2016). The impact of competitive advantage, customer satisfaction and customer relationship management on customer loyalty: an empirical analysis of banking sector of Pakistan. Singaporean Journal of BuSineSS EconomicS, and Management StudieS (SJBem), 5(3), 31. https://www.singaporeanjbem.com/pdfs/SG_VOL_5_(3)/2.pdf

Hoang, T. P. (2018). Factors affecting service quality at Vietnamese retail banks. Banks and Bank Systems, 13(2), 39-48. http://dx.doi.org/10.21511/bbs.13(2).2018.04

Hong, W., Zheng, C., Wu, L., & Pu, X. (2019). Analyzing the Relationship between Consumer Satisfaction and Fresh E-Commerce Logistics Service Using Text Mining Techniques. Sustainability, 11(13), 3570. https://doi.org/10.3390/su11133570

Huang, S.-P. (2016). A study on the effects of emotional intelligence and workplace friendship on job satisfaction and performance of employees in micro-enterprises. Journal of interdisciplinary mathematics, 19(3), 567–583. https://doi.org/10.1080/09720502.2016.1196050

Ibojo, B. O., & Asabi, O. M. (2015). Impact of customer satisfaction on customer loyalty: A case study of a reputable bank in Oyo, Oyo State, Nigeria. International Journal of Managerial Studies and Research, 3(2), 59-69. https://www.arcjournals.org/pdfs/ijmsr/v3-i2/6.pdf

Jerônimo, T. de B., Medeiros, D. (2014). Measuring quality service The use of a SERVPERF scale as an input for ELECTRE TRI multicriteria model. International Journal of Quality & Reliability Management, 31(6), 652-664. https://doi.org/10.1108/ijqrm-06-2012-0095

Kotler, P., Keller, K. L. (2012). Administração de Marketing. [Tradução de Sônia Midori Yamamoto]. 14. ed. São Paulo: Pearson Education do Brasil.

KPMG International Research (2020). Customer experience in the new reality Global Customer Experience Excellence research 2020: The COVID-19 special edition. https://assets.kpmg/content/dam/kpmg/es/pdf/2020/11/global-customer-experience-excellence-2020.pdf

Lee, J. L.-M., Siu, N. Y.-M., & Zhang, T. J.-F. (2020). Face, fate and brand equity: service recovery justice and satisfaction. The Journal of Consumer Marketing, 37(7), 843–854. https://doi.org/10.1108/jcm-01-2019-3037

Lewis, B.R. & Mitchell, V.W. (1990). Defining and Measuring the Quality of Customer Service. Marketing Intelligence & Planning, 8(6), 11-17. https://doi.org/10.1108/EUM0000000001086

Li, J., Zhou, J., & Cheng, Y. (2022). Conceptual method and empirical practice of building digital capability of industrial enterprises in the digital age. IEEE transactions on engineering management, 69(5), 1902–1916. https://doi.org/10.1109/tem.2019.2940702

Lima, M., & Fernandes, T. (2015). Relationship Bonds and Customer Loyalty: A Study Across Different Service Contexts. Springer International Publishing Switzerland, 326-339. https://doi.org/10.1007/978-3-319-14980-6_26

Liu-Thompkins, Y., Khoshghadam, L., Attar Shoushtari, A., & Zal, S. (2022). What drives retailer loyalty? A meta-analysis of the role of cognitive, affective, and social factors across five decades. Journal of Retailing, 98(1), 92–110. https://doi.org/10.1016/j.jretai.2022.02.005

Lokesh, S., Menaga, A., Vasantha, A. (2022). Influence of customer relationship management towards customer loyalty with mediating factor customer satisfaction in insurances sector. Quality - Access to Success, 23(187). https://doi.org/10.47750/qas/23.187.21

Ma, R., & Wang, W. (2021). Smile or pity? Examine the impact of emoticon valence on customer satisfaction and purchase intention. Journal of Business Research, 134, 443–456. https://doi.org/10.1016/j.jbusres.2021.05.057

Ma, Y., Ding, J., & Hong, W. (2010). Delivering Customer Value Based on Service Process: The Example of Tesco.com. International Business Research, 3(2). https://doi.org/10.5539/ibr.v3n2p131

Mahmoud, M. A., Hinson, R. E., & Anim, P. A. (2018). Service innovation and customer satisfaction: the role of customer value creation. European Journal of Innovation Management, 21(3), 402–422. https://doi.org/10.1108/ejim-09-2017-0117

Mainardes, E. W., Ferreira, J., & Raposo, M. L. (2014). Strategy and Strategic Management Concepts: Are They Recognised by Management Students? E+M Ekonomie a Management, 17(1), 43–61. https://doi.org/10.15240/tul/001/2014-1-004

Martínez, R. (2016). Servicio al cliente interno: todos somos clientes y todos tenemenos clientes. Bogotá: Ediciones de la U.

Meenakshy, M., & Srivastava, M. (2022). An insight into the drivers of electronic word of mouth in tourism. International Journal of Public Sector Performance Management, 9(1/2), 144. https://doi.org/10.1504/ijpspm.2022.119832

Mello, E., M., Curth, M., Gonçalves, M. A., & Paulo Joaquim Salvador, R. (2021). O comportamento do consumidor no mercado fitness: físico x virtual. Revista Gestão e Desenvolvimento, 18(3), 26–50. https://doi.org/10.25112/rgd.v18i3.2750

Monteiro, A. P.S. (2016). O Processo de Fidelização de Clientes: O caso cartão Continente. Dissertação [Mestrado em Gestão e Estratégia Empresarial]. https://bityli.com/RKWua

Mukthar, K.P.J., Asis, H.R., Carcamo, J.E.V., Zarzosa-Marquez, E.D., Soto, R.M.H. (2023). Application of Innovative Technology in Textile Retail for Enhanced Customer Service and Business Development. In: Alareeni, B., Hamdan, A. (eds). Explore Business, Technology Opportunities and Challenges ‎After the Covid-19 Pandemic. ICBT 2022. Lecture Notes in Networks and Systems, 495. Springer. https://doi.org/10.1007/978-3-031-08954-1_3

Mutua, P. M. (2020). Customer Service Strategy and competitive advantage of Getrudes’Children’s Hospital. Dissertação [Mestrado em Gestão de Negócios]. https://bityli.com/IApcI

Nielsen (2015). Looking to achieve new product success? Listen to your consumers. https://bityli.com/wWIvP

Ordoñez-Velez, K., & Zaldumbide-Peralvo, D. (2020). La calidad del servicio al cliente como ventaja competitiva en las microempresas de servicio. Digital Publisher CEIT, 5-1(5), 4–15. https://doi.org/10.33386/593dp.2020.5-1.310

Performance Research Associates. (2011). Atendimento nota 10. Tudo o que você precisa saber para prestar um excelente serviço e fazer com que os clientes voltem sempre. Rio de Janeiro: Editora Sextante.

Poor, M. H. Poor, M. A., & Darkhaneh, M. A. (2013). The quality of service and its importance in service organizations. Arabian Journal of Business and Management Review, 3(3), 34 – 37. https://www.arabianjbmr.com/pdfs/OM_VOL_3_(3)/4.pdf

Queiroz, L. S., Bergamo, F. V. M., & Melo, J. S. (2016). Validação de um Modelo Conceitual de Experiência de Compra Online para Consumidores Brasileiros. Revista Brasileira de Marketing, 15(4), 524-539. https://doi.org/10.5585/remark.v15i4.3407

Rapert, I. M., & Wren, B.M. (1998). Service quality as a competitive opportunity", Journal of Services Marketing, 12(3), 223-235. https://doi.org/10.1108/08876049810219539

Redda, E. H., & North-West University, South Africa. (2020). The influence of utilitarian and hedonic consumption values on consumer attitude towards online shopping and purchasing intentions. Journal of reviews on global economics, 9, 331–342. https://doi.org/10.6000/1929-7092.2020.09.32

Ribeiro, O M. (2007). Qualidade no atendimento ao cliente como estratégia competitiva. [Dissertação de mestrado, ISCTE Business School]. https://core.ac.uk/download/pdf/38680012.pdf

Rodríguez, I. J. C., & Figueroa, J. G. (2019). Determinantes del comportamiento de queja del consumidor en México. Acta Universitaria, 29, 1–17. https://doi.org/10.15174/au.2019.2076

Rosa, A. P., & Deluca, M. A. M. (2015). Qualidade no atendimento como vantagem competitiva. Revista Eletrônica Ciências da Administração e Turismo, 3(3), 16-27. http://incubadora.periodicos.ifsc.edu.br/index.php/ReCAT/article/view/341/16-27

Sangtani, V., & Murshed, F (2017). Product knowledge and salesperson performance: rethinking the role of optimism. Marketing Intelligence & Planning, 35(6), 724-739. https://doi.org/10.1108/MIP-11-2016-0199

Santos, M.; Torres, K.A.; Silva, L. H. A.; Borba, E. L. (2019). Satisfação de clientes: ánalise do atendimento prestado pelas empresas no comércio de São João Del Rei- MG. Anais do XIV Simpósio de Excelência em Gestão e Tecnologia – SEGeT, AEDB, Rio de Janeiro.

SBVC - Sociedade Brasileira de Varejo e Consumo. (2021). O Papel do Varejo na Economia Brasileira. Atualização 2021. https://sbvc.com.br/wp-content/uploads/2021/04/O-Papel-do-Varejo-na-Economia-Brasileira_2021-SBVC-5.pdf

Siggelkow, N. (2007). Persuasion with case studies. Academy of Management Journal, 50(1), 20-24. https://doi.org/10.5465/AMJ.2007.24160882

Silva, K. A. da ., Teixeira, Érica ., & Soares, U. G. . (2020). A influência do layout como fator de crescimento nas vendas no varejo: um estudo de caso na empresa Realce Moda e acessórios em João Pinheiro-MG. Scientia Generalis, 1(1), 22–37. http://scientiageneralis.com.br/index.php/SG/article/view/v1n1a3

Silva-Treviño, J. G., Macías-Hernández, B. A., Tello-Leal, E., & Delgado-Rivas, J. G. (2021). La relación entre la calidad en el servicio, satisfacción del cliente y lealtad del cliente: un estudio de caso de una empresa comercial en México. Ciência UAT, 15(2): 85-101.

ssOtica. (2022). Pesquisa Mercado Óptico Brasileiro 2022. https://drive.google.com/file/d/1T8e438mpcib2ziXxYLRS_xl7X4Ra8m3z/view

Tarziev, V., Banabakova, V., & Georgiev, M. (2018). Customer Service Standards. IJASOS- International E-Journal of Advances in Social Sciences, 49–55. https://doi.org/10.18769/ijasos.415520

Triviños, A. N. S. (1987). Introdução à pesquisa em ciências sociais: a pesquisa qualitativa em educação. São Paulo: Atlas.

Unes, B. V. J., Camioto, F. C., & Guerreiro, E. D. R. (2019). Fatores relevantes para a fidelização de clientes no setor bancário. Gestão & Produção, 26(2), e2828. https://doi.org/10.1590/0104-530X2828-19

Vergara, S. C. (2015). Métodos de Pesquisa em Administração. 6ª ed. São Paulo: Atlas.

Voss, C., Tsikriktsis, N. & Frohlich, M. (2002). Case research in operations management. International Journal of Operations & Production Management, 22(2), 195-219. https://doi.org/10.1108/01443570210414329

Wieseke, J., Geigenmüller, A., & Kraus, F. (2012). On the Role of Empathy in Customer-Employee Interactions. Journal of Service Research, 15(3), 316–331. https://doi.org/10.1177/1094670512439743

Yang, R. (2017). Influence of customer to customer interaction on service purchase behavior intention: Moderating role of customer experience—in China E-commerce environment. In Proceedings of the Fourth International Forum on Decision Sciences (p. 261–270). Springer Singapore.

Yeboah, J., & Ewur, G. D. (2014). Quality Customer Service as a Competitive Advantage in the Telecommunication Industry in the Western Region of Ghana. Journal of Education and Practice, 5(5), 20. https://www.iiste.org/Journals/index.php/JEP/article/view/10950

Yin, R. K. (2015). Estudo de caso: planejamento e métodos. 5. ed. Porto Alegre: Bookman.

Zanelli, J. C. (2002). Pesquisa qualitativa em estudos da gestão de pessoas. Estudos da Psicologia, 7, 79-88. https://www.scielo.br/j/epsic/a/GdRk6zHHNz4yL6NBsH6P4yH/?format=pdf&lang=pt

Zilber, M. A., & Lazarini, L. C. (2005). Vantagem Competitiva e Fidelização do Cliente: Um Estudo sobre Planos de Saúde. Anais do Segundo Encontro de Estudos em Estratégia – 3es da ANPAD. http://www.anpad.org.br/admin/pdf/3es2005-288.pdf