The Power of Pre-Mortems

A pre-mortem works much like Janis's advice. Before acting on a decision, the group imagines it has already failed and works backward to explain why. That gives everyone permission to voice concerns in the hypothetical rather than as a personal challenge.

It also shifts the social dynamic. Instead of one person disagreeing with the group, everyone hunts for risks at the same time, so criticism becomes a shared task rather than an act of dissent.

Gary Klein, who popularized the technique, points to research finding that imagining an outcome in advance raises people's ability to spot reasons for failure by about 30%.