Before starting a project, assume it has failed and work backward to identify what went wrong, surfacing risks that optimistic planning overlooks.
The pre-mortem is one of the few practical debiasing strategies Kahneman recommends. Instead of asking 'What could go wrong?' (which triggers defensive optimism), assume failure has occurred and ask 'What did go wrong?' This reframing overcomes the planning fallacy and overconfidence by legitimizing skepticism and encouraging team members to voice concerns. The technique works by shifting from inside view (our specific plan) to outside view (what typically goes wrong in similar projects).
Before launching a product, a team assumes it failed spectacularly and generates reasons: 'The market wasn't ready,' 'Competitors copied us faster,' 'Manufacturing costs exceeded projections.' This surfaces risks that optimistic planning would have missed.
Asking 'What could go wrong?' is sufficient—the pre-mortem's power comes from assuming failure, which overcomes defensive optimism and legitimizes skepticism.
Logically equivalent choices produce different decisions when framed differently (as gains vs. losses, or with different reference points).
PrincipleContinuing an endeavor because of previously invested resources (time, money, effort) that cannot be recovered, even when continuing is irrational.
PrincipleFast, automatic, unconscious cognitive processing that operates through pattern recognition and associative memory without deliberate effort.
Mental ModelSlow, effortful, conscious cognitive processing required for complex calculations, unfamiliar tasks, and deliberate reasoning.
Mental ModelThe tendency to rely too heavily on the first piece of information encountered (the anchor) when making decisions, even when it's arbitrary or irrelevant.
PrincipleJudging the frequency or probability of events by how easily examples come to mind, leading to overestimation of vivid, recent, or emotional events.
PrincipleJudging probability by similarity to stereotypes or prototypes, while ignoring base rates and sample size.
PrincipleWhen faced with a difficult question, System 1 automatically substitutes an easier question without conscious awareness of the switch.
FrameworkBefore starting a project, assume it has failed and work backward to identify what went wrong, surfacing risks that optimistic planning overlooks.
Before launching a product, a team assumes it failed spectacularly and generates reasons: 'The market wasn't ready,' 'Competitors copied us faster,' 'Manufacturing costs exceeded projections.' This surfaces risks that optimistic planning would have missed.
Asking 'What could go wrong?' is sufficient—the pre-mortem's power comes from assuming failure, which overcomes defensive optimism and legitimizes skepticism.
Pre-Mortem is explored in depth in "Thinking, Fast and Slow" by Daniel Kahneman. Distilo provides a deep AI-powered analysis with key insights, audio narration, and practical frameworks.