Hand hygiene remains the single most effective measure to prevent hospital acquired infection and yet poor compliance is reported repeatedly. Nurses represent the largest labour group and perform the greatest amount of direct patient care in the contemporary National Health Service. They receive their initial hand hygiene training in the pre-registration curriculum within a competence framework based on knowledge, skills and attitudes. The pre-eminent training method is one that delivers behavioural competence, making the tacit assumption that compliance will follow. In this study a mixed methods approach demonstrated that students overestimated their knowledge and skills, found it difficult to give an objective account of their performance, and reported an improbable level of compliance. The reasons why people can be self serving in their judgements may be due to information processing errors, exacerbated by the model of education and training. Flawed self assessments may present major barriers to improved performance if students view their compliance as better than it actually is. Conceptualising hand hygiene as a taxonomy of learning and introducing the cognitive strategies of reflection and self assessment would better enable students to problem solve, seek out new information, draw on past experience and gain greater and deeper understanding of the complex topic of hand hygiene behaviour.