Tell Me About a Technical Decision You Made That Turned Out to Be Wrong
Behavioral and LeadershipFailure and OwnershipAsked atSeniorStaffUpdated
“Tell me about a technical decision you made that turned out to be wrong. What was the impact and what did you learn?”
They're checking whether you own mistakes and learn from them. Strong answers have a real cost, a clear cause, and a change in how you decide that you still use.
Rubric by Level
Junior
- Picks a real mistake with a real effect, even a small one.
- Owns it without blaming the reviewer or the ticket.
- Names what you'd check next time.
Mid
- Names the impact, like time lost, a bug in production, or rework.
- Explains the signal you missed and why you missed it.
- Describes a change you made, like a test or a review step.
Senior
- A real failure with real consequences, like cost, an outage, or a missed quarter.
- Owns the decision without blaming teammates, process, or unknown unknowns.
- Gives a specific root cause: the signal you should have weighed more.
- Names the process change that followed, like design reviews, load tests, or a smaller blast radius.
Principal
- The bet was large and long, and you explain how you knew to stop or change course.
- Describes how you made it safe for the org to learn from it in public.
- Shows how the lesson changed the way the company places technical bets.
Red Flags
- Failure that's not really a failure ('I worked too hard').
- Blame deflection.
- No mechanism added to prevent recurrence.
Follow-Ups to Expect
- How did you tell the people who were affected?
- What would have helped you catch it a month earlier?
A Story Shape That Holds Up
The Call
What you decided and what you expected to happen.
What Went Wrong
The cost, with a number if you have one.
Why
The signal you missed and why you missed it.
What Changed
The process change you still use.