What
The pre-mortem (coined by Gary Klein) is a prospective failure analysis technique. Before starting a project, assume it has catastrophically failed. Ask: "It is 6 months from now. This project failed completely. Why?" List every plausible cause and rank by likelihood × impact. This technique works because prospective hindsight activates different reasoning than standard risk analysis — people are more honest about failure causes when asked "why did it fail" vs "what might go wrong."
Steps: (1) State the goal clearly. (2) Fast-forward to failure. "It failed. What happened?" (3) List all causes — suppress optimism bias, allow pessimism. (4) For each top-3 cause, add a mitigation to the plan now.
When to Use
Use pre-mortem before any significant project, feature launch, or deployment. It is especially valuable in high-stakes situations where optimism bias might cause teams to underweight tail risks.
How
- State the goal clearly.
- Fast-forward: assume the project has failed completely.
- List every plausible cause, suppressing optimism bias.
- Rank causes by likelihood × impact.
- Add mitigations for the top 3 causes to your plan.
- Beware the anti-pattern: only planning for success and ignoring tail risks.