A key event that quietly stops recording is one of the most expensive bugs in analytics, because it corrupts your reporting and starves Google Ads of the signal it bids on. Here is a systematic way to find why conversions are missing and fix it.

First, the terminology

Since March 2024, GA4 calls them key events, not conversions; conversion now refers to a key event you import into Google Ads. So missing conversions usually means one of two things: the key event is not recording in GA4, or it records in GA4 but does not reach Google Ads. Work out which layer is broken before you dig.

Step 1: Confirm the event fires at all

Start in DebugView, which shows events from your own session in real time. Enable debug mode and trigger the action:

// Force events into DebugView for this session
gtag('config', 'G-XXXXXXXXXX', { debug_mode: true });
gtag('event', 'generate_lead', { value: 10, currency: 'USD' });

If the event does not appear in DebugView, the problem is collection – the tag or trigger is not firing – not GA4 itself.

Step 2: Check it is marked as a key event

An event can fire perfectly and still not count as a conversion if no one flagged it. In Admin, open Key events and confirm the event name is toggled on. A common failure is a renamed or newly added event that was never marked.

Step 3: Trace the collection path

If the event is missing from DebugView, walk the chain:

  • Confirm the GA4 tag or gtag snippet actually loads on the page.
  • In GTM, check the trigger conditions and that the tag is published, not just in preview.
  • Verify the event name matches exactly, since GA4 is case-sensitive and a typo creates a separate event.
  • Rule out an ad blocker or consent denial suppressing the request.

Step 4: Check the GA4-to-Ads handoff

If the key event is healthy in GA4 but conversions are missing in Google Ads, the break is in the import. Confirm GA4 and Google Ads are linked, the key event is imported as a conversion action, and enough time has passed, since Ads conversions can lag. Remember the counts will never match exactly, because Ads attributes by click date within its window while GA4 counts by event date.

Common root causes

Most missing-conversion tickets come down to a short list:

  • The event was never marked as a key event.
  • A GTM change sits in preview and was never published.
  • An event-name typo or casing mismatch split the data.
  • Consent denial or ad blockers dropped the hit.
  • The Google Ads link or conversion import was never completed.

A key event that silently stops recording poisons both your reports and your bidding, which is why it is worth chasing methodically. Confirm it fires in DebugView, check it is marked as a key event, trace the collection path, and verify the Ads import. Work the layers in order and the missing conversion stops being a mystery and turns back into a number you can trust.

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