Tell me about the most serious data incident you've owned. What happened, how did you communicate it, and what changed afterwards?

What the interviewer is looking for

• This question tests ownership & incident response. Owns failures end to end: assesses impact, tells affected people early, fixes the root cause and adds safeguards afterwards.
• What to bring out: Fast detection and impact assessment, early honest updates, root cause fix, blameless review and lasting prevention steps.
• Expect a follow-up like: Looking back, what would you do differently now?

Another way it may be asked: Think of a time bad or missing data reached people who relied on it. Walk me through how you handled it from start to finish.

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 ownership & incident response 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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