Abstract
Before a project starts, people tend to keep their doubts to themselves. The plan hangs together and everyone wants it to work. A pre-mortem asks the team to assume it has already failed and to explain what went wrong.
Because the failure is taken as given, pointing out a problem counts as helping. Research on prospective hindsight suggests that imagining an outcome as certain helps people come up with more reasons for it. You end up with a ranked list of risks, each with someone responsible for it.
Method
- 01
Brief the plan
Make sure everyone knows the goal and the timeline. Keep it short.
- 02
Jump ahead to the failure
Say that it's now some months later and the project has failed badly. Nobody debates whether it failed, only why.
- 03
Write reasons alone
Give everyone a few minutes to write down every reason they can think of before anyone speaks.
- 04
Collect them one at a time
Go round the group, one reason per person per turn, until the lists run out. Start with the most junior person.
- 05
Rate and rank
Score each reason for likelihood and impact, then multiply the two to rank the risks.
- 06
Plan the response
For each of the top risks, agree how to reduce it and who owns it. Note an early warning sign to watch for as well.
When to use it
- Before you commit serious time or money to a project.
- When a plan has a lot of momentum and nobody is questioning it.
- Before a launch or a migration, or anything else that's hard to undo.
Common pitfalls
- Running it after the plan is locked, when nothing can change.
- Letting the most senior person speak first and set the tone.
- Collecting risks with no owner and no warning sign, so nothing happens afterwards.
- Listing only outside causes. Include the failures that would be your own fault.
Origin and references
Attributed to Gary Klein (2007).
- Klein, G. (2007). Performing a project premortem. Harvard Business Review, 85(9).
- Mitchell, D. J., Russo, J. E., & Pennington, N. (1989). Back to the future: Temporal perspective in the explanation of events. Journal of Behavioral Decision Making, 2(1).
- Kahneman, D. (2011). Thinking, Fast and Slow. Farrar, Straus and Giroux.