Why interviewers ask this
When an interviewer says tell me about a time you made a decision with incomplete information, they are checking whether you can describe the shape of the hole. Everybody makes decisions without full information, constantly, and saying so demonstrates nothing at all. What separates people is whether they knew which specific facts were missing at the moment they decided, whether they made any attempt to close the gap in the time available, and whether they held any honest sense of how likely they were to be wrong. Candidates almost always describe the decision and then the outcome, because both are easy to narrate and the outcome usually flatters them. They almost never describe the hole. The hole is the only part of this that transfers to a job, since the next decision will have a different shape and a different set of things you cannot see.
An answer that sounds fine
We needed to pick a payments provider before our contract with the old one expired, and we had about three weeks. Two candidates came through the shortlist and the pricing was similar. I could not get a full picture of either one's reliability because neither would share incident history under an evaluation agreement, so I went with the one that had better documentation and a named integration contact. I made the call, we signed, and the migration went through in five weeks with no major issues beyond a couple of reconciliation errors in the first month that we caught quickly. It was a good lesson in moving decisively when you do not have everything you would like, because waiting for perfect information would have meant running past the contract expiry.
Where it breaks
The last sentence is doing something the rest of the answer has not earned. Moving decisively when you do not have everything you would like is a slogan, and it appears here in place of the actual reasoning, which is nowhere in the account. He names one missing item, incident history, and then the story simply proceeds as though naming it was the same as handling it. There is no attempt described to get it another way, through a reference call or a mutual customer or a trial period with a break clause. There is also no sense of how exposed he thought he was. An interviewer listening to someone answer tell me about a time you had to make a decision with incomplete information wants the gap quantified, because a person who cannot say how uncertain they were is a person who was not tracking it.
The follow-up
What information did you wish you had, and what was your confidence, as a number?
Incident history, mostly, and a sense of how they behaved during one. I did ask a contact at another company who used them, and he said they had a bad outage the year before, which I sort of discounted because it was second hand. Confidence, maybe seventy percent. Honestly it was probably closer to fifty and I would not have said fifty out loud at the time because I had recommended them.
Both halves of that are more valuable than anything in the prepared version. He had partial information and discounted it because it was inconvenient rather than because it was unreliable, which is an ordinary failure and one he can now name. The number is the more revealing half. He held roughly fifty percent confidence and reported seventy, to himself as much as to anyone else, because he had already put his name to the recommendation. That is the mechanism by which organisations make bad decisions confidently, and it is almost never dishonesty. It is the ordinary pull of having already put your name on something. A candidate who has caught himself doing it once is considerably safer than one who has never gone looking.
An answer that holds up
I had three weeks to choose a payments provider before our contract lapsed, and neither shortlisted supplier would share incident history under evaluation terms. What I wanted was their outage record for the previous eighteen months. What I did was call two mutual customers, and one of them told me the provider I preferred had a significant outage the year before. I discounted that because it was second hand, which was the wrong reason, and I should have discounted it less or gone back for detail. I recommended them anyway and I told my director I was around seventy percent confident. My actual confidence was closer to half. I negotiated a six month break clause, which was the part I got right, and the migration ran clean. Since then I write the number down before I say it out loud, because the gap between those two is where I was fooling myself.
The interviewer asks what he did to close the gap.
Two reference calls with mutual customers, one of which handed me the answer, and I talked myself out of it because it was second hand. The break clause was the real hedge. If I had rated my own confidence honestly at the time I would have pushed harder on that outage instead of moving past it.
Practice this question
Say your answer to this question out loud, then get asked what your confidence was as a number. Answer it now, free, no account.
Related questions
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