Usability Evaluation of Self-Ordering Kiosks in Fast Food Restaurants

In recent years, the introduction of technology and digital management into the service industry has gradually changed consumers' lifestyles. With the popularization of equipment systems, the development and use of self-ordering kiosks have gained much attention in the restaurant industry. However, the utilization rate of self-ordering kiosks has been meager since their establishment, and they cannot relieve the queues at the counter. This study investigates whether self-ordering kiosks in fast food restaurants can meet customers' needs to achieve a self-ordering process and improve ordering efficiency.This study was conducted on three representative fast-food chains in Taiwan, and their self-ordering kiosks were used as the target of the investigation. Thirty participants with no experience were invited to conduct an ordering task experiment to evaluate the ease of use of the ordering interface. The experiment was divided into five contextual tasks: meal selection, modifying the order, changing the meal comment, self-checkout and selecting receipt type, and redeeming e-coupon. All procedures were conducted on the self-ordering kiosk in the fast-food restaurant. The evaluation methods were as follows: 1) the participants performed the tasks sequentially and recorded the time performance, and conducted think-aloud during the tasks; 2) the participants filled out SUS and QUIS questionnaires to indicate their evaluation and feelings about the self-ordering kiosk; 3) semi-structured interviews were conducted to understand the participants' operation and future expectation during the tasks.The results showed that in the operation of the self-ordering kiosk in all three fast-food restaurants, there were cases of incorrect interface operation by the participants. We found that: 1) 33% of the participants indicated that they were unclear about the operation process, and the kiosk prompts were not clear enough to cause uncertainty among the participants. In particular, when an error occurred and it was necessary to go back to the previous step, the prompts in the system interface were ineffective in helping the participants operate smoothly, resulting in a long ordering time. 2) All three self-ordering kiosks use 21.5-inch upright touch screens and a full-page interface design, making it easy for the participants to ignore the information and hardware devices below the interface when operating at close range. For example, 37% of the participants said they could not find the shopping cart at the bottom of the interface and could not confirm the scanner's location the first time when redeeming the e-coupon. 3) 73% of the participants said in the questionnaire that the function of customizable meals is essential, but the degree of customization in the current self-ordering kiosk is relatively low. Finally, the SUS scores of the three quick-service restaurants' self-service ordering kiosks were 56.25 (F grade), 62 (D grade), and 56 (F grade), respectively, which did not meet the ease of use criteria. The results of this study helped to understand the operational behavior of the participants in using the self-ordering kiosks.