Tell me about a time you caught an error in data or a report before anyone else noticed.

What the interviewer is looking for

• This question tests attention to detail. Reconciles figures against trusted sources, tests edge cases and catches errors before users do.
• What to bring out: Specific example, how the anomaly was spotted, root cause, communication and a fix that prevented recurrence.
• Expect a follow-up like: What did you put in place so it wouldn't happen again?

Another way it may be asked: Think of a moment you spotted something off in the numbers. How did you notice and what did you do?

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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