Each platform had its own attribution definition wired in. None of the definitions had been mapped against each other. GA4 was running a default last-non-direct-click model. Meta was running a seven-day-click, one-day-view model. Shopify Marketing was running its own session-stitching against UTM tagging. The cart-abandonment tool was running a seven-day post-email window. The four windows alone, ignoring everything else, would have produced disagreement.
Beneath the windowing, the conversion definition itself differed. Meta counted a "conversion" against pixel events. Shopify counted a "conversion" against an order record. GA4 counted a "conversion" against a configured event. The cart-abandonment tool counted a "conversion" against any order following an email send. Three of the four definitions were upstream of the order record. One was the order record itself.
- GA4 attribution model · last-non-direct-click, session-based
- Meta attribution model · 7-day-click, 1-day-view, pixel-based
- Shopify Marketing · UTM-driven, order-record-based
- Email tool · 7-day post-send window, send-event-based
- Auto-tagging · on for Google Ads, off for Meta, partial for email