Whenever you're ready, walk me through how you'd approach this.
If a critical metric drops by 10% overnight, what is your systematic approach to identifying the root cause? Explain how you would first validate that the movement is real, then decompose it across relevant dimensions and distinguish data-quality issues from genuine business changes. Describe the analyses, tools, stakeholders, and follow-up actions you would use. State how you would communicate findings and prioritize remediation.