When missteps, mistakes and failures happen, it's helpful to diagnose what went wrong in order to ensure better execution next time, but it's too easy to quickly fall in to the trap of pointing fingers and assigning blame.
FIRST RULE OF BUSINESS: Assign blame.
Leaders are measured by the size of their shoulders. Insecure leaders point downwards, calling out how others missed the mark. Confident leaders accept responsibility for others' actions taken on their team. This classic quote from Bear Bryant sums it up nicely.
Effective leaders get the blame out of the way early, so the focus can shift from who to what. "Who screwed up?" is not productive. "What went wrong?" is.