``Erasing the Echo'': The Usability of Data Deletion in Smart Personal Assistants

Smart home personal assistants (SPAs) have gained widespread popularity in recent years. Despite their widespread adoption, existing research indicates that many users remain unaware of how to delete from these devices. While data deletion has been explored in other contexts, in the context of SPAs it is not well understood. This paper addresses this gap by investigating users' understanding of data deletion in the context of SPAs and evaluating the usability of existing deletion mechanisms. To address this, we conducted an interview study with 20 Amazon Alexa and Google Home users, during which we also observed their interactions with deletion processes. Our findings reveal that users hold diverse mental models regarding data deletion, recovery, and data storage, often leading to uncertainty and a lack of confidence in the deletion process. Moreover, we identified several usability challenges, particularly when users attempted to delete data using voice commands. Based on these insights, we discuss the implications for the design of more effective and transparent data deletion mechanisms in SPAs.