“More” is not necessarily “better.” Many corporations request employees to provide cordial services to customers and emphasize the service attitude of “customer first.” However, additional services are not necessarily applauded by customers if the customers do not appreciate the additional services; hence, additional services may cause opposite effects. Customers are believed to be more concerned with whether service providers effectively solve their problems than whether they work hard to provide customer delight [1].

A study on “over attentive” restaurant services showed that customer satisfaction may not increase proportionally with thorough and attentive services [2]. Thus, uninvited visit by servers may be considered excessive and unnecessary. Customer satisfaction mainly depends on customers’ interaction with front-line employees; therefore, over-service can easily result in customer perception of dissatisfaction. A study explored compensational services at restaurants and noted that excessive compensational services cause discomfort and anxiety in customers [3].

Customers may consider that the excessively high-quality services are unnecessary. Over attentive waiting staff has been named as the most irritating practice in British restaurants. Nearly half (49 per cent) of the diners surveyed said that servers topping up already full glasses of wine, take away plates while they are still chewing or repeatedly interrupting to ask if everything is okay deterred them from leaving a tip [4]. Hence, merely aiming at exceeding customer expectations without addressing their needs would only increase the distance between customers and service providers and adversely affect the standard of service by shifting its focus from customer satisfaction. Sun and Chiu studied the root cause of over-service conducted by service personnel in restaurants [5]. Over-service was defined as the provision of services that exceed customer expectations or simply the provision of services that customers deem redundant, thus resulting in negative customer perceptions. Sun, Huang and Chiu explored over-service in hotel guest services and showed that over-service in hotels include proactively handling luggage on behalf of customers; unilaterally offering concierge service; frequently inquiring stay satisfaction; frequently providing advertisement materials; providing excessively detailed explanations; and providing excessive courtesy [6]. Behaviors of over-service can be categorized into “excessive frequency,” “over speediness,” “over attentiveness,” “over decorativeness,” “over enthusiasm,” “over caring,” and “excessive detail” [7].

The present study focused on front desk service in hotels; the Kano model was used to analyze the relevance between categorization of hotel service quality and over-service experiences. Furthermore, the ZOT was used to examine the shift in perceptions when customers experience over-service at front desks.

Application of the kano model

Kano, Seraku, Takahashi and Tsuji considered two aspects of any given quality attribute: an objective aspect, involving the fulfillment of quality, and a subjective aspect, involving the customers’ perception of satisfaction [8]. Through this model, quality attributes can be divided into five categories: attractive quality attribute, which is a positive attribute that does not induce dissatisfaction if absent; one-dimensional quality attribute, which is a positive linear graph in the Kano model, and the higher the perception of a quality attribute is, the greater the satisfaction becomes; must-be quality attribute, which induces dissatisfaction if absent but does not contribute to customer satisfaction when present; indifferent quality attribute, which does not cause any satisfaction or dissatisfaction to customers regardless of whether it is present; and reverse quality attribute, which causes customer dissatisfaction when present.

When a specific questionnaire is used, quality attributes can be classified into the five aforementioned dimensions. The questionnaire contains pairs of customer requirement questions. For example, “How do you feel if a given feature is present?” and “How do you feel if that given feature is absent?” Responses to both the functional and dysfunctional forms of the question are required for the classification of customer perceptions. The classification is then applied to an evaluation table in which each customer requirement can be classified into one of five dimensions. 

The Kano model was published more than 30 years ago, but it remains a very popular theory that is used by researchers in hospitality and tourism management. For example, Mati and Jardan used the Kano model to analyze the factors determining urban tourists’ satisfaction [9]. On the basis of the Kano model, Zobnina and Rozhkov examined the customer satisfaction drivers of Russian tourists while choosing hotels in Europe. The study revealed groups of customer satisfaction drivers by their effects from attractive to expected and indifferent, in addition to presenting customer preference profiles by age, overall travel experience, and purpose of trip [10].

Chiang Chen and Hsu highlighted and categorized the technological innovation attributes of hotels based on the Kano model [11]. Four technological innovation factors were identified: use of the Internet and apps, use of smartphones as a room key and for payment, e-housekeeping, and use of electronic self-service systems. Borgianni and Rotini noted that Kano theory analyzes only the current situation. Analysis of only the current situation limits the use of Kano surveys for long-term design projects. They proposed a quantitative reference model linking the performance of quality attributes to the ensuing satisfaction, thus providing a clear picture of the transformation of customer requirements. They suggested the importance of performing repeated tests with the same group of customers, considering uncertainties related to the output of Kano surveys [12].

Several scholars have attempted to improve the applicability of the Kano model by using other management theories. For example, Pai, Yeh, and Tang examined how each item of service quality may exhibit different effects on customer satisfaction in the chain restaurant industry [13]. They combined the Kano model and importance-performance analysis (IPA) to investigate the critical service quality attributes in the chain restaurant industry. Dipietro, Khan and Bufquin proposed the application of a Kano-simultaneous importance-performance analysis (SIPA) integration model to compare the performance of quality attributes for fast food restaurants [14]. The use of such a model enables management teams to draw useful conclusions about the level of their customers’ satisfaction and how their position in comparison with their competition. A Kano-SIPA integration model was considered more effective and comprehensive than any of the IPA, Kano, or SIPA models individually. Madzik systematically analyzed the three most frequently used modifications of the Kano model and proposed a new approach: Type IV [15]. The proposed approach is based on a modification of the process of requirement categorization intended to minimize the discrepancy zone between the calculated and the real position of a particular requirement. The author suggested that this approach significantly improved the accuracy of requirement categorization without increasing difficulty for the customer.

Although several new approaches in using the Kano model have emerged, the basic concept of the model remains unchanged. The use of qualitative methods to comprehensively explore customers’ over-service perception by following the Kano questionnaire can challenge the long-term belief in the model.

Adequate and desired expectation

ZOT theory outlines perceptual zones of “adequate and desired” in the context of service quality provision [16]. The theory articulates that customer expectations are dynamic. Enterprises should provide customers with services that exceed adequate expectations in order to maintain competitiveness. Furthermore, if enterprises can provide services exceeding desired expectations, customer loyalty becomes sustainable. This theory has been widely used in recent years by researchers to explore the level of customer satisfaction and loyalty. For example, Hsieh, Sharma, Rai and Parasuraman conducted a study at a call center of a telecommunications firm to determine the effects of internal IT service quality on the quality of services provided by employees to external customers as well as on customer satisfaction with and the use of the deployed technology [17]. They found that internal IT service quality affected employees’ service quality. Employees’ satisfaction with technology changed more dramatically near the adequate service level than near the desired service level. Stodnick and Marley performed a longitudinal analysis of the ZOT. They found the ZOT model to be a significantly more effective predictor of changes in customer satisfaction than the traditional linear model [18]. This study demonstrated to practicing managers that they do not need to micromanage service delivery; preventing service failures is more crucial than micromanaging service delivery.

Prior research on the ZOT has mostly focused on business-to-consumer service perspectives. Ho, Sharma and Hoise extended research on the ZOT to the perspectives of business-to-business professional services (professional audit firms and their clients) [19]. They found service tenure to positively affect both desired service and adequate service levels. Notably, the ZOT concept and other management theories have been combined to synthesize an effective research approach. Chen proposed a model for evaluating service quality based on competitive ZOT by benchmarking against competitors and then constructed an analytical framework referred to as competitive ZOT service quality-based IPA for prioritizing quality improvements of quality attributes [20]. Chen, Chen and Su proposed an innovative framework that integrates the advantages of IPA, the ZOT concept, and the Kano model [21]. A case study conducted in a wealth management department in the banking industry demonstrated the effectiveness of the proposed methodology. The results indicated that the proposed approach recommends optimal service strategies to managers and outperforms traditional IPA.

In summary, assessment of desired and adequate expectations is an idea that has been frequently used for monitoring service performance and customer satisfaction. ZOT theory is based on the expectancy disconfirmation concept that post purchase satisfaction occurs if a product or service outperforms expectations. Nevertheless, the construct of over-service has not been considered. Considering the aforementioned studies, the present study did not only apply the viewpoint of over-service to examine the Kano model but also integrated the ZOT to obtain insight into the process of attitude shift of customers when they experience over-service.

The study participants were customers of five-star hotels as documented by the Taiwan Bureau of Tourism. The interviewees were aged ≥18 years with five-star hotel boarding experience within the previous year. The sampling method was based on snowball sampling with recommendations and referrals from interviewees for subsequent interview participants. Two pretest interviews were conducted to assess the clarity of the questionnaire, suitability to the participants, time required to complete it, and other possible problems. After revising the questionnaire wording and the semi structured interview questions, a total of 26 questionnaires were completed, and 26 interviews were conducted. In this study, the Kano questionnaire measurement was used for quantitative analysis because the items of measurement were based on those in the Taiwan 5-Star Hotel Assessment Indicators, which assess the services offered by front desk staff. After the participants completed the questionnaires, semi structured interviews were conducted to determine the participants’ experiences and perceptions of over-service and its correlation with the attributes of the questionnaire. The interview outlines are presented as follows:

• Please share your experiences of interaction with front desk staff during your stay at the hotel.
• Please describe your experiences of over-service related to the outlined survey items, if any.
• When you experienced over-service, what were your thoughts?

After categorization of quality attributes with the Kano model, the interview content was compiled into transcripts and coded categories; subsequently, it was analyzed to obtain the results of this study. To ensure the credibility of this study, the interviews were recorded in written and audio format; the participants’ verbal responses and experience descriptions were transcribed, and rationalized articulations of their responses were provided.

Quality attributes categorization

Because the participants had varied perceptions of quality attributes from the questionnaire, the attribute categorization process was based on the most frequently mentioned attributes. Attractive quality was identified to include the following: “provision of appropriate recommendations to customers,” “familiarity of in-house facilities,” “recommendations of visiting attractions outside the hotel and neighboring areas,” and “provision of the latest printed guide and map.” Therefore, the absence of these services was implied to not have resulted in customer dissatisfaction because the presence of these services brought customer delight or surprise. Attributes such as “confirmation of customer names,” “wearing professional attire,” “relaying messages to customers within 15 minutes of query reception,” “inquiring about customer stay experiences,” and “invitation for future patronage when checking out” were classified under the indifferent dimension. The absence of these services was implied to not have directly affected customer satisfaction.

The must-be quality dimension comprised two attributes: “providing warm and friendly greeting and service” and “confirming customer room number and name when checking out.” The absence of these services was implied to result in customer dissatisfaction, whereas provision of these services would be taken for granted without increasing customer satisfaction. “Keeping reception desk neat and clean,” “appropriately receiving and processing request and complaints,” and “providing quick check-out service” were considered to constitute one-dimensional quality attributes. Improving these service areas would result in a consequent increase in customer satisfaction (Table 1).

Table 1: Kano Quality Attribute Analysis.

Over-service experiences were collected through in-depth interviews; the interview content was reflected in the survey questions for subsequent articulation. The interviewees mentioned seven instances of experiences of over-service. The interview transcript analysis is provided as follows. Inquiring about a guest’s needs and providing the appropriate service: “When asked about handling my luggage, I was OK with him asking me once, but when I declined, I didn’t like the fact that, he asked again to help me, which made me feel unsafe” (I2-OS1). Proactively offering service: “Regarding check-in, I think the over-service was due to the fact that they did too much; they asked us to sit on the lobby sofa while preparing refreshment drinks for us and at almost the same time verified our booking information” (I23-OS14). Using appropriate phone etiquette and using pleasant tones for customer delightful: “When staying in the hotel, they just bombard you with so many pleasant greetings, which I really had no patience for” (I25-OS17).

Familiarity with hotel facilities and giving appropriate recommendations: “They spend a lot of time explaining where to have breakfast, the opening hours of all the facilities, I could have just read it in the in-room printed guide, as I just wanted to quickly get to my room” (I18-OS10). Providing recommendations for touring neighboring areas and points of attraction. “I just wanted to check-out the neighboring eateries, and because he described in over-detailed fashion, it made my choices even more difficult, as I just needed a suggestion of general directions; I can decide for myself” (I12-OS7). Providing the latest printed guide or map: “At check-in, I was offered the local map, and replied that I will get it after I came back down, but he still placed three maps on desk, which made me feel pressured” (I5-OS2). Thanking guests and inviting them to visit again next time. “There were so many people thanking me for my stay, but it was indeed a little overwhelming and embarrassing” (I21-OS12).

Previously, quantitative analysis was often used to categorize Kano’s attributes. However, through the interviews, we found that the investigation of quality factors could not be limited to the result of questionnaire analysis; quality factors require further investigation into the respondents’ over-service experiences. After articulation with the viewpoint of over-service, the over-service experiences were distributed over the attractive quality, one-dimensional quality, indifferent quality, and must-be quality attributes.

The attractive quality attributes were determined to be “recommending facilities in and outside hotel” and “providing guides and map.” Most interviewees stated that if these services were offered, satisfaction enhancement would result. Conversely, if they were offered excessively, a negative perception of pressuring would result. The one-dimensional quality attributes were determined to be “front desk staff proactively offering services.” Some interviewees mentioned that the constant supply of service, especially during check-in, such as “offering refreshment drinks and further explanations,” caused mental fatigue and discomfort. In the must-be quality attributes, some interviewees indicated that the greeting of front desk staff seemed excessively long and made customers feel impatient. The indifferent quality attributes were determined to be “thanks for guest coming” and “invite to visit again next time.” The interviewees indicated that after checking out, they were greeted farewell by a group of hotel staff, which made them feel appreciated but also made them feel embarrassed. In this study, over-service experience was not related to reverse quality attributes because the interview participants did not recognize the existence of reverse quality attributes in the survey questions.

Over-Service analysis and ZOT

Based on the interview, the range of negative moods subject to over-service was identified; the range comprised feeling pressured, perceived waste of time, discomfort, insecurity, anger, and loss of patience. The feedback indicated that front desk staff eagerly performed their service without considering customer needs, which completely negated the core meaning and value of their primary service intention. Customer perception of over-service in one hotel stay period can be divided into singular over-service experience and multiple over-service experiences. The perceptions can be further articulated into tolerable and intolerable. The interview transcript analyses are provided as follows (*R = Researcher): “After all, it was out of goodwill, so it was hard to turn down, but over-service put me in a difficult catch-22 situation, as neither refusal nor acceptance was desirable for me, as I was dreading the conversation when I returned, as they would ask me where I went or didn’t go” (I12-OF7). “[R: How did you feel when you experienced impatience on the phone?] Yes, I did feel impatient [R: Was that acceptable?] I found it unacceptable, as I thought it was a waste of time” (I23-OF16). Most participants considered over-service to be within their tolerance. However, if service failure (performance lower than expectation) occurred during the same stay at the hotel, over-service was considered intolerable. The customer would combine all experiences into the same single negative perception. “Although his explanation was too long, I was happy with the amenities, so I will still stay in the hotel next time. But if service was not good and the amenities were not attractive enough, I will regard his long explanation as unacceptable” (I22-B12).

In addition to the perception of experiencing multiple over-services, the participants indicated that their stay was subject to a barrage of over-service which gradually shifted their tolerance feedback from tolerable to intolerable. For example, being greeted by multiple staff members; being offered multiple guides, maps, and newspapers on many occasions; and excessively long phone greetings would result in negative feelings. If several over-service instances occurred in a single stay in a hotel, the customers would perceive the service as complicated and would not consider future patronage. “Next time, I would choose an average commercial hotel, instead of these complicated five-star hotels (in which guests are greeted by multiple staff members upon check-in, multiple checks on luggage assistance are provided, guests are greeted on the phone, and guests are given things not needed). In this stay, as opposed to my previous experience in hotels of listening to my needs, the greeting persisted and interrupted my expression of needs, which was unpleasant for me” (I5-OF2-5) (Figure 1).

Figure 1: Over-service and ZOT.

For focusing on the shift in customer perception of over-service, the present study deviated from conventional practice of the Kano model and ZOT, which entails only using quantitative analysis for result affirmation. The study adopted a qualitative method by adding the over-service construct. Our study showed that over-service experiences pertain to four of Kano’s quality dimensions, namely one-dimensional quality, attractive quality, indifferent quality, and must-be quality attributes. When integrated over-service experience with the ZOT, we observed that customer perception exhibited a direct or gradual shift into negative perception, which resulted in shifts from the tolerable to the intolerable category.

Although each customer typically recognizes and perceives service quality differently, this study proposes two implications for managing service quality: managing service quality relevance and timeliness of service rendered. The results of this study highlight the importance of timely service provision in comparison with the provision of excessive services to customers. Providing customers with unnecessary or excessive services would occasionally cause an adverse effect and reduce the repurchase intention of customers. Each customer perceives over-service differently, from slightly negative perceptions to extremely negative perceptions. In five-star hotels, offering customized service is imperative for competition. However, over-service behaviors continue in those hotels. Therefore, managers should consider the measurement of service quality from different perspectives and effectively use human resources and training to improve service quality.

If researchers seek to articulate over-service behaviors, the study population can be limited to the employees of certain departments. Such studies can not only clarify the relationship between differentials among customer service expectations and service behavior provision but also provide an in-depth perspective on the service behavior of service professionals at certain levels. The present study can be extended to the behavior of over-service from the viewpoint of service professionals in order to establish a comprehensive theoretical viewpoint of over-service. Additional studies should be conducted to verify the shifts in customers’ perceptions when they encounter over-service in order to generate a comprehensive theoretical paradigm.

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