The Voice System of the Future: Research on the Development of Usability Evaluation Metrics and Improvement Strategies for AI Speaker Voice User Interfaces – Focusing on Generation Z in China

Voice User Interfaces (VUIs) are emerging as a key technology for next-generation human–computer interaction. However, limited research has examined usability criteria tailored to Generation Z users in the context of AI speakers. This study developed and validated a set of usability evaluation metrics through a comprehensive approach, including literature review, user interviews, expert focus groups, Analytic Hierarchy Process (AHP), and usability testing. The findings indicate that voice interaction efficiency was rated as the most important criterion, followed by comprehensibility, information quality, operational feedback, error handling, user satisfaction, and task discoverability. These dimensions were further divided into 24 subcriteria. In addition, the study proposes strategies to improve VUI usability, such as designing more human-like dialogues and incorporating emotional responsiveness. The results contribute to a deeper understanding of VUI usability for Generation Z and offer practical recommendations for AI speaker developers aiming to enhance user experience.