Sometimes provocative, sometimes charming, Nick Leeson, a self-proclaimed “former rogue trader,” recounted his time at Barings Bank in the early 90s, outlining his wrongdoings and the lack of reaction by his colleagues that led to the collapse of the bank. Speaking at a conference in Luxembourg late last month, he took responsibility for some of his actions, while scorching his colleagues by name, in the process, for their incompetence.