Tell me about a technical decision you made that turned out to be wrong.
- Technology:
- Behavioral
- Experience:
- Senior
Quick answer
Explain the original reasoning, the evidence that changed your view, how you corrected course and what decision-making practice improved afterwards.
What the interviewer is evaluating
- Intellectual honesty
- Decision quality
- Learning mindset
How to structure your answer (STAR)
- Situation: decision and assumptions.
- Task: achieve the desired outcome.
- Action: response when evidence changed.
- Result: correction and process improvement.
Example answer
I chose an implementation approach that looked simpler for the initial feature but became difficult once a second workflow required different data access patterns.
When the new requirement exposed the limitation, I compared the cost of continuing versus changing the boundary and recommended a small refactor before adding more behavior.
The lesson was to test important architectural assumptions against likely second use cases instead of optimizing only for the first feature.
Discussion
This tests intellectual honesty and the ability to update your beliefs when reality disagrees with your assumptions.
Do not rewrite the story as if the decision was obviously correct. Explain what information was available at the time and what you missed.
The strongest answers show a change in process, such as better experiments, metrics or review criteria.
Key points
- Own the decision
- Explain original assumptions
- Recognize evidence
- Improve the decision process
Common mistakes
- Claiming the failure was someone else鈥檚 fault.
- Pretending the decision was not actually wrong.
- Giving no change in future behavior.
Follow-up questions
- What signal should you have noticed earlier?
- How do you avoid repeating this type of mistake?