A pre-mortem is a structured exercise in prospective hindsight. Instead of asking 'what could go wrong?' — a question that tends to produce optimistic, incomplete answers — it asks you to imagine that the initiative has already failed and to work backwards to understand why.
The technique was developed by psychologist Gary Klein and has been validated by research showing that prospective hindsight — imagining a future event as if it has already happened — significantly improves the ability to identify reasons for that event. In plain terms: it is easier to explain a failure that has already occurred than to predict one that might.
To run a pre-mortem, gather the people who will be responsible for the initiative. Ask each person to spend five minutes writing down all the reasons the initiative might have failed, imagining it is twelve months from now and the initiative has not achieved its goals. Then share the lists and discuss.
The most valuable outputs are the failure modes that appear on multiple lists — the risks that multiple people independently identified. These are the ones most worth addressing. They are also often the ones that were not being discussed openly, because the social dynamics of planning tend to suppress pessimism.
A pre-mortem is not about killing initiatives. It is about improving them. The goal is to identify the most significant risks before you commit, so you can either mitigate them or make a more informed decision about whether the risk is worth taking.
The pre-mortem is most valuable when it is run by someone who is genuinely open to changing the plan based on what they hear. A pre-mortem run as a formality, where the conclusions are predetermined, is worse than not running one at all — it creates the illusion of rigor without the substance.
