Platform dashboards and internal models rarely line up on day one. The gap is rarely "someone is wrong"; more often definitions, lookback windows, and identity graphs diverge in boring, fixable ways. Start by aligning on the counting object: is the platform counting clicks while your model counts assisted conversions with a different half-life?
Second, document the time window mismatch. Weekly business rhythms often truncate journeys that your exploratory model keeps whole. That truncation changes credit dramatically in considered purchases. Third, separate reconciliation work from storytelling work—reconciliation belongs in a spreadsheet appendix, not an executive headline.
Finally, schedule a recurring forum where channel owners can bring counterexamples without being treated as hostile to analytics. The goal is shared vocabulary, not instant numeric alignment.