Daily orders dropped 20% yesterday. Walk me through how you would investigate.

What the interviewer wants to hear

• First confirm the drop is real and not a data or tracking issue
• Check for external factors such as holidays or outages
• Segment by platform, region, channel and new vs returning users
• Look at the funnel to find which step fell
• Check recent releases or campaigns
• Communicate findings and next steps quickly

Model answer

First I check whether the drop is real. Did the pipeline load fully, did a tracking event change, is the dashboard using a partial day? I compare with the source system if possible. If it is real, I check context: a holiday, a competitor sale, a payment gateway outage or a weather event. Then I segment: by platform (Android, iOS, web), app version, region, traffic channel, and new versus returning customers. Usually the drop is concentrated in one segment, for example only Android users on the latest version. Next I walk the funnel, from visits to product views to cart to payment, to find which step fell. I check the release and campaign calendar for changes. Once I find a likely cause, I share a short update with the evidence, my confidence level and who should act, and keep monitoring.

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