Having succeeded in being selected for medical school, medical students are not always familiar with failure and yet they are expected to graduate prepared to effectively function in the failure burdened arena of clinical medicine. Lacking in the developing literature on learners and failure is an exploration of how this transformation is accomplished. The purpose of this study was to examine how medical students perceive and experience failure during their medical school training.We used a qualitative description methodology to probe the failure experiences of medical students attending a Canadian medical school. Participants were provided with the broad definition of failure used in this research: "deviation from expected and desired results". Twelve students were sampled, three from each of the four years of study, and participated in individual, semi-structured interviews that were analyzed using thematic analysis to identify and describe core themes.At the start of medical school, students admitted limited experience with failure; their early descriptions were self-centred and binary. Personal stories recounted by preceptors encouraged students and helped them understand that physicians are human and that failure is inevitable. Students felt relatively protected from failures that could impact patients. Both witnessing and participating in a failure event were distressing and sometimes at odds with their expectations. Students expressed a desire to talk about the experience.Medical students described examples of failure experience during medical school that transported them from the more certain black and white beginnings of their classroom into the uncertain shades of grey of clinical medicine. What the participants heard, saw and experienced suggests opportunities for classroom teachers to better prepare preclinical students for the inevitability of failure in clinical medicine and opportunities for clinical teachers to engage in open, inclusive conversations surrounding failures that occur on their watch.