Assume they are right and find out what you asked for that you did not mean. Sit with the engineers and get the estimate broken down, because the cost is usually one requirement you would happily trade away, like real time sync or a full history migration. Re-scope against the thin version, then decide with real numbers instead of negotiating the estimate down.
Why interviewers ask this
Interviewers use this to see whether you treat engineering as a partner or an obstacle. The tell is what you do first: haggling over the number is the wrong instinct, and asking for a breakdown is the right one. They also want to hear that you know your own requirements are often the expensive part, and that you take a genuine three months back to stakeholders honestly rather than committing anyway.
How to structure your answer
- Start by trusting the estimate rather than challenging it.
- Ask for a breakdown to find the expensive requirement.
- Re-scope by trading away the costly item, not by pressuring the team.
- If the estimate holds, take the real number back to stakeholders.
Example answer
I start from the assumption that they are right and that I asked for something I did not mean. So I sit down with the engineers and get the three months broken into pieces, and almost always most of the time sits in one or two requirements I would happily trade. On a project like that the cost turned out to be real time sync across devices, which I had put in the doc almost casually. Nobody had asked for it. We shipped with a refresh on open and it went from months to weeks. If the breakdown does not reveal anything like that, then the estimate is real and my job changes. I go back to the stakeholders with the actual cost and we decide whether the outcome is worth three months, or whether there is a thinner version worth doing first. What I try never to do is negotiate the number down, because that just moves the surprise to the end.
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See how it worksFollow-up questions to expect
- How do you handle an engineer who always estimates high?
- What do you do when the breakdown reveals unavoidable platform work?
- How do you communicate a three month build to a stakeholder expecting three weeks?
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