TL;DR
If conversions stop recording, the ad platform keeps optimising against an incomplete signal. Check the conversion action fires on the live site every month, compare platform conversions against the CRM, and pause or rework a campaign after a long tracking gap rather than assuming it will recover.
How a tracking break misleads bidding
Ad platforms bid toward the actions you told them matter. When that feed goes quiet, the system does not stop spending. It keeps buying traffic and learns from a thinner picture, so it drifts toward whatever still produces a signal, which is often the cheapest and least valuable click.
The damage compounds because the platform reports its own view of conversions. If the tag stopped firing, the report looks like performance fell, when in fact the measurement broke.
Monthly checks that catch it early
- Submit a test conversion on the live site and confirm it appears in the platform
- Compare platform conversion counts against the CRM or order system for the same period
- Confirm the tag still fires after a theme, plugin or checkout change
- Check that consent settings have not blocked the tag for a large share of visitors
- Watch for a sudden step change in conversion rate, which usually means tracking, not demand
Recovering a campaign that learned the wrong signal
Fix the tracking first and confirm real conversions are flowing again. Then decide whether the campaign can be salvaged. A short gap is usually recoverable. A long gap leaves the bidding model trained on the wrong behaviour, and a fresh campaign with a clean history often performs better than nursing the old one.
Keep a note of the date the tracking broke. When you compare periods later, that date explains the anomaly without guesswork.