Skip to content
ENRU
All exercises
ChallengeExecuteLow

Premortem

Assume the plan failed and identify plausible mechanisms, indicators and countermeasures.

30–50 min6–16

Purpose

Reduce overconfidence and reveal failure knowledge before commitment.

Output: Prioritised risk register with indicators and owners

Materials

  • Plan summary
  • Failure cards
  • Risk register

Preparation

  • Choose a concrete plan with defined outcome and horizon.
  • Clarify that the exercise does not replace formal risk or safety analysis.

Facilitation steps

1

Imagine failure

8 min

State that the plan failed by the target date; write plausible reasons silently.

2

Cluster mechanisms

10 min

Group causes by mechanism without deleting minority risks.

3

Prioritise

10 min

Select risks by impact, plausibility and detectability.

4

Design control

12 min

Name an indicator, owner, prevention or response for each priority risk.

Observe

  • Are uncomfortable risks softened?
  • Do causes describe mechanisms rather than vague failure?
  • Is an owner named?

Debrief

  • Which risk changed the plan?
  • What early signal would we monitor?
  • What risk must be escalated outside this session?

Transfer to work

Add indicators and owners to the implementation plan and review them at the next checkpoint.

A premortem surfaces plausible failure mechanisms; it does not calculate probability or replace specialist controls.

Failure modes

  • The list is exhaustive but unprioritised.
  • Participants treat imagined failure as evidence that failure is certain.

Accessibility

  • Use silent written generation before speech.
  • Provide a non-alarmist framing and clear boundaries.