Overview: Premortem versus Postmortem
A decision postmortem looks back after the fact, to reflect on what worked and didn’t work as a way to enable future improvement.
A premortem is, in general terms, the opposite of a postmortem. It takes place at the beginning of a project, or decision. What makes a premortem powerful is the framing—you assume failure. With defeat solidly in mind, you take a hard look at what went wrong—and then develop strategies that could have prevented this outcome.
Decreases failure due to blind spots—no project leader/decision maker can see everything—and cognitive biases, including overconfidence
Enables us to measure the magnitude of threats we may already be worrying about
Enables all team members to share concerns and areas of potential weakness
Breaks up groupthink by applauding dissenting or questioning views
Heightens teamwork, as now everyone is fighting for the win together
Increases team productivity
Research has shown that we have a 30% chance of correctly identifying future outcomes when we imagine that an event has already occurred—as done in premortems.
1989 study conducted by Deborah J. Mitchell, of the Wharton School; Jay Russo, of Cornell; and Nancy Pennington, of the University of Colorado