What do usability evaluators do in practice?

Think-aloud testing is a widely employed usability evaluation method, yet its use in practice is rarely studied. We report an explorative study of 14 think-aloud sessions, the audio recordings of which were examined in detail. The study shows that immediate analysis of observations made in the think-aloud sessions is done only sporadically, if at all. When testing, evaluators seem to seek confirmation of problems that they are already aware of. During testing, evaluators often ask users about their expectations and about hypothetical situations, rather than about experienced problems. In addition, evaluators learn much about the usability of the tested system but little about its utility. The study shows how practical realities rarely discussed in the literature on usability evaluation influence sessions. We discuss implications for usability researchers and professionals, including techniques for fast-paced analysis and tools for capturing observations during sessions.