The CEO asks: "Why are customers churning?" How do you approach this?

What the interviewer wants to hear

• Define churn precisely and measure the trend
• Segment by cohort, plan, channel, region
• Look at behaviour before churn and exit reasons
• Separate correlation from causation
• Recommend actions and tests

Model answer

First I define churn clearly, for example "no purchase in 60 days" or "subscription cancelled", and check how the rate has changed over time using retention curves by signup cohort. Then I segment: by plan, acquisition channel, region, device and tenure, to see where churn is concentrated. Often one segment, like users from a discount campaign, explains most of it. Next I look at behaviour before churn, such as fewer logins, support tickets or failed payments, and combine this with qualitative data like cancellation reasons and support conversations. A churn model with SHAP can show which factors predict churn, but I am careful to say these are associations, not proven causes. I finish with prioritised recommendations, such as fixing failed payment retries, and propose experiments to confirm the biggest drivers.

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