Audit plan (end-to-end):1) Define scope & success criteria- Confirm exact LTV formula used (gross vs. net, revenue vs. margin), CAC definition, and timeframe stakeholders expect.2) Data collection checks- Inventory sources (orders, refunds, returns, discounts, customer table, ad spend).- Verify event-level completeness: row counts by day, compare expected vs. actual (ingestion gaps).- Check IDs: customer_id consistency, duplicate accounts, anonymized keys.Quick SQL checks:sql
-- missing customer IDs
SELECT COUNT(*) FROM orders WHERE customer_id IS NULL;
-- duplicate accounts
SELECT customer_id, COUNT(*) FROM customers GROUP BY 1 HAVING COUNT(*)>1;
3) ETL / transformation review- Trace revenue from raw events to dashboard: aggregation logic, joins, dedup rules.- Inspect date alignment (order_date vs. event_date vs. attributed_date), timezone shifts.- Confirm refund/chargeback subtraction and delay handling (e.g., 30/60/90-day return window).- Validate attribution: first-touch vs. last-touch vs. multi-touch; verify ad spend allocation matches.4) Cohort definitions & lookback windows- Ensure cohorts are defined by consistent anchor (acquisition date = first paid event).- Test multiple lookbacks (30/90/365 days) and show cumulative LTV curves; low LTV could arise from too-short or overly-long windows or mis-assigned cohort membership.- Segment by channel, campaign, and geography to find concentrated issues.5) Assumptions to verify- Churn and retention handling, sample size filters, treatment of inactive accounts, currency conversions, customer lifetime modeling methods (historical vs. predictive).- Check if refunds were double-counted or excluded; whether lifetime value uses revenue or margin.6) Root-cause triage- Run delta analysis: compare dashboard numbers vs. source-system aggregates by cohort and period; identify where divergence first appears (raw → ETL → model → viz).7) Presenting findings & fixes- Deliver a concise executive summary: key issue(s), impact (e.g., LTV understated by X%), and confidence level.- Visuals: side-by-side tables showing source vs. dashboard, cumulative LTV curves by cohort, and funnel of where value was lost.- Action plan with owners and timelines: e.g., fix ETL join by EOD, recompute LTV with refunds included, or change attribution rule and re-run historical metrics.- Recommend monitoring: automated validation queries, unit tests in ETL, and a data contract for product/marketing to prevent recurrence.This approach surfaces whether the low LTV is a data/ETL bug, definition mismatch, or a true business trend, and produces prioritized, testable fixes.