Pre-Mortem
Assume the decision failed twelve months from now — and write the story of why before you commit.
The only decision tool that pays you to argue against yourself.
A pre-mortem inverts the post-mortem: the failure is the premise, not the question.
A pre-mortem inverts the post-mortem. Instead of examining a failure after it happens, you assume the failure has already happened, and work backwards to find why. The inversion matters because it changes what the mind is permitted to see: asked whether a decision might fail, a person defends it; told it has failed and asked to explain, the same person produces reasons they were unable to name a moment earlier. It is the only decision tool that pays you to argue against yourself.
Four questions, in this order.
Name the decision plainly first. Everything after is written from a future in which it has already failed.
The failure story
It is twelve months from now. This decision failed — not ambiguously, clearly. Write what happened, as you would explain it to someone who must understand what went wrong.
The assumption that broke
Which assumption broke first? The belief that turned out to be wrong — stated plainly.
The silent witness
Who saw it coming and said nothing — and what stopped them? A person, a signal, a data point you dismissed.
Month zero
What would you have needed to see today, before committing, to catch it? The evidence or question that would have changed your mind.
The examination is conducted by the person who made the decision.
That is not dishonesty. It is the ordinary architecture of a mind protecting a conclusion it has already reached.
The difficulty with examining a decision you have already made is that the examination is conducted by the person who made it. Every question you ask is answered by the part of you that has an interest in the answer. This is not dishonesty. It is the ordinary architecture of a mind protecting a conclusion it has already reached.
The pre-mortem works by removing the thing being protected. If the decision has already failed — if that is the premise, not the question — then there is nothing left to defend, and the reasons become available. People who could not name a single serious risk five minutes earlier will produce four, specifically and without hesitation.
The output is not a prediction. It is a list of the assumptions that were carrying more weight than anyone had noticed.
One further use: the artifact this produces is worth sharing with the person who will bear the decision’s consequences alongside you — a co-founder, a partner, a board. Not to persuade them. To find out whether the failure story you wrote is the same one they would have written.
Your pre-mortem is sealed at close, next to your forecasts.
So the outcome can be read against what you said would kill it — not against what you remember saying.
Written from the future
You state the failure as though it already happened. The reasons arrive far more readily than they do forward.
It surfaces the unnamed
The assumption you would not volunteer is usually the first thing a pre-mortem produces.
Recorded with the audit
Your pre-mortem is sealed at close, next to your forecasts — so the outcome can be read against it.
A pre-mortem assumes a decision has already failed and works backwards to explain why. Rather than asking whether a plan might fail — which invites defence — it treats the failure as established and asks for the cause, which makes risks available that the deciding mind would otherwise suppress.
A post-mortem examines a failure that has occurred, when the cost has already been paid and the analysis can change nothing about the decision itself. A pre-mortem performs the same examination before commitment, when the findings are still able to alter the outcome.
Assume it failed. Now say why.
The pre-mortem is free and needs no account. Inside an audit it is sealed with your forecasts at close.