Decision-making, in the interview
The pre-mortem: imagine the failure before it happens
A pre-mortem starts from the assumption that a plan has already failed, then asks everyone to explain why. Working backward from a failure surfaces risks that optimism hides. In an interview, it is the strongest way to show you plan for things going wrong, not only for things going right.
How does Pre-mortem work?
- Assume the project or the deal has failed, a year from now.
- List every reason it could have failed. Get each person to write theirs alone first.
- Rank the reasons by likelihood and impact.
- Build the defenses into the plan now: owners, early warnings, a fallback.
When does Pre-mortem fit an interview question?
Use it for questions about making a plan, a launch or a partnership hold: "how would you make sure this succeeds?", "what could go wrong?". It also helps with a difficult vendor or partner: plan now for the renewal where you may need to walk away.
What does a strong answer with Pre-mortem sound like?
Question: an external partner on a long contract is delivering poor work that threatens your team's output.
"I would run a quick pre-mortem: it is a year from now and this partnership has failed. Why? Most likely, quality kept slipping because nothing was measured, and we had no alternative at renewal. So today I set specific quality metrics and a formal improvement plan with them, add our own review of their work, and start assessing other vendors before the renewal comes up."
Common mistakes
- Turning it into a list of every possible risk, with no ranking and no action.
- Running it in a group without letting people write alone first, so the loudest voice sets the list.
- Using it after the decision, as a post-mortem, when it no longer changes anything.
Where does Pre-mortem come from?
The psychologist Gary Klein described the method in the Harvard Business Review article "Performing a Project Premortem" (2007). It draws on research into prospective hindsight: imagining that an event has already happened makes people better at identifying its causes.
Practice with this framework
These problems from the free GCA practice set are best answered with Pre-mortem. Pick the framework that fits each one, then read the worked answer.
1 questions, one at a time
Pick a pace. The timer stops when you check an answer, and the worked method opens straight away. Nothing is saved or sent anywhere.
Keys: 1 to 4 pick an option, Enter checks and moves on.
One question, two answers
A weak answer, why it scores low, and the strong one. Under a minute each.
The partner you can't fire
Pre-mortem: FAQ
What is the difference between a pre-mortem and a post-mortem?
A post-mortem looks back at a failure that has happened. A pre-mortem imagines the failure before the project starts, so the causes can still be prevented.
How long does a pre-mortem take?
Klein's version takes under an hour: a few minutes of silent writing, a round where everyone shares one reason at a time, then a review of the plan. In an interview answer it takes three sentences.
The other decision frameworks
- Reversible vs irreversibleDecide fast when a choice can be undone, and slow down for the ones that cannot (Jeff Bezos' one-way and two-way doors).
- Regret minimizationAsk which you would regret more in the long run: doing it, or not doing it (Jeff Bezos).
- CynefinFirst name the situation: clear, complicated, complex or chaotic. In a crisis, act first; in a complicated case, analyze first (Dave Snowden).
- Expected valueWeigh each outcome by its odds: the chance of a gain times its size, minus the chance of a loss times its size.
- WRAPWiden your options, reality-test your assumptions, attain distance, prepare to be wrong (Chip and Dan Heath).
- 10/10/10Ask how the choice will look in 10 minutes, 10 months and 10 years (Suzy Welch).
- The 70% ruleDecide once you have about 70% of the information you wish you had, then adjust as you learn (Jeff Bezos).
- OODA loopObserve, orient, decide, act, and loop again faster than the situation changes (John Boyd).