alawein premortem
Use this before a plan, launch, or migration that is hard to undo. Assume it already failed, then
work backward to causes you can still prevent. grill and self-refute attack something that
already exists. premortem looks ahead.
When to use it
- Before committing to a plan, launch, or migration that is hard to reverse.
- When the cost of a wrong assumption is high enough to pay for prevention now.
- Skip it for a small, reversible change.
Required inputs
- The plan, in enough detail to name its assumptions and dependencies.
- The stakes and the rough timeline, so failures can be ranked by likelihood and impact.
Steps
- Set the scene. State the plan in one line and a date by which it has failed: "it is four weeks out and this migration has gone badly."
- List the causes. Name how it failed: the broken assumption, the slipped dependency, the production edge case, or the team that was not looped in.
- Rank by likelihood times impact. Use that ranking to decide what to prevent first.
- Turn the top causes into actions. For each high-rank cause, name the cheapest preventive step or the early warning signal that would catch it.
Output format
- Failure modes: a small table of cause, likelihood, impact, and prevention.
- Actions: the two or three preventive steps worth taking now, before committing.
Stop conditions
- A premortem that ends with fears and no actions is incomplete. Name the actions.
- This is read-only. It names risk and prevention; it does not change the plan on its own.
- Stop once the top causes each have a prevention or a watch signal.