The increase in health problems due to smoking or lack of physical activity has created the incentive to develop a virtual coach to help people with smoking cessation and increase physical activity. In this study, a mixed-methods analysis (thematic analysis, quantitative analysis, and a literature study) was carried out to find out what the reasons are for wanting to stop or continue using this virtual coach. By using triangulation, themes were found. The three themes found are the authenticity of the interaction, the caring character of the virtual coach, and the content of the interactions. Based on these themes, recommendations have been given on how to improve the virtual coach. The recommendations suggested are to improve the interactivity of the chat between the virtual coach and the participants, tailor the content of the interactions to the participant’s personal needs, and make use of gamification approaches to increase motivation.