If inquiries are about learning the lessons of the past, why do they appear to find the same failings time and again? Bristol, Mid Staffordshire, Morecambe Bay, Liverpool Community Health are all examples of where culture went wrong. The lack of learning from inquiries is a prominent concern and one raised elsewhere in this issue. In this article, I explore why it might be that culture is repeatedly found to be the cause of healthcare failures. I start by reviewing perspectives on what culture is and the degree to which it is possible change it. I examine how culture was described in the Bristol, Mid Staffordshire, Morecambe Bay and Liverpool inquiries and question whether these are the same cultures with the same problems or whether they are different. I discuss possible explanations for apparent similarities, describe how cultural change occurs and conclude by drawing out the implications of focusing on culture as a threat to patient safety.