> Instead of asking what might go wrong, in a pre-mortem we assume that the project has failed, and the question is what did go wrong. The difference might appear subtle, but the change in mindset is actually profound. This illusion of outcome certainty makes it safe for those who are knowledgeable about the initiative and concerned about its weaknesses but reluctant to share to speak up (especially about the types of things that are uncomfortable or awkward to talk about). Also, working backwards from a known outcome (i.e. asking why something did happen rather than why it might happen) is a great way to spur the team’s creativity and imagination.  [source](https://www.infoq.com/articles/transformation-by-imagining-it-had-failed/)