Tell me about a bug you caught that others had missed. What made you look there?

What the interviewer is looking for

• This question tests attention to detail. Notices small inconsistencies, checks assumptions, and gives examples of catching what others missed.
• What to bring out: A specific bug, a curious or risk-based reason for looking, careful verification, and its impact if it had shipped.
• Expect a follow-up like: Did you turn that into a test or checklist so it would not happen again?

Another way it may be asked: Think of a time you found a problem that slipped past everyone else. How did you spot it?

A structure to follow: STAR, with the weight on Action and Result

1. Step 1

   Situation

   One or two sentences: where, when and what was at stake. Pick a real example you were close to.

2. Step 2

   Task

   What you personally were responsible for. Say "I", not only "we", so the attention to detail you showed is visible.

3. Step 3

   Action

   The two or three things you did and why you chose them over the alternatives. This should be about half your answer.

4. Step 4

   Result

   What changed, in your own measure of it, and what you would do differently. Only use numbers you can stand behind.

This is guidance on shape, not a script. Use your own real experience and facts; never invent details to fill a gap. See the STAR guide and answer frameworks.

Common slips

• Describing what the team did without saying what you did.
• Choosing an example with no clear outcome, or one you cannot answer detailed questions about.
• Ending on the action and skipping the result and what you learned.

How to practise it

Write two bullet points for each STAR letter, then say the answer aloud in about two minutes.

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