The duty to protect patient welfare underpins undergraduate medical ethics and patient safety teaching. The current syllabus for patient safety emphasises the significance of organisational contribution to healthcare failures. However, the ongoing over-reliance on whistleblowing disproportionately emphasises individual contributions, alongside promoting a culture of blame and defensiveness among practitioners. Diane Vaughan's 'Normalisation of Deviance' (NoD) provides a counterpoise to such individualism, describing how signals of potential danger are collectively misinterpreted and incorporated into the accepted margins of safe operation. NoD is an insidious process that often goes unnoticed, thus minimising the efficacy of whistleblowing as a defence against inevitable disaster. In this paper, we illustrate what can be learnt by greater attention to the collective, organisational contributions to healthcare failings by applying NoD to The Morecambe Bay Investigation. By focusing on a cluster of five 'serious untoward incidents' occurring in 2008, we describe a cycle of NoD affecting trust handling of events that allowed poor standards of care to persist for several years, before concluding with a poignant example of the limitations of whistleblowing, whereby the raising of concerns by a senior consultant failed to generate a response at trust board level. We suggest that greater space in medical education is needed to develop a thorough understanding of the cultural and organisational processes that underpin healthcare failures, and that medical education would benefit from integrating the teaching of medical ethics and patient safety to resolve the tension between systems approaches to safety and the individualism of whistleblowing.