Define and validate product metrics

For a new product feature, define the core business metrics (north-star and guardrail). Explain how you would instrument events, create a tracking plan, and derive KPIs from raw data. Describe how you would sanity-check metric correctness, set thresholds, and investigate anomalies. Discuss how metric definitions differ across batch versus streaming views and how you would communicate caveats and data latency to stakeholders.