Meta optimised for a form that no longer existed — three months of ghost leads

The situation

A commercial real estate firm in Australia had been running Meta lead gen campaigns for 6 months. Their CRM showed 40 leads per month. Their Meta dashboard showed 180 leads per month. The sales team was frustrated — most "leads" never existed.

The problem

Eight months earlier, the website had migrated to a new CMS. The old contact form URL was decommissioned but the Meta pixel event tied to that URL still fired whenever anyone hit the old 404 page. The 404 page was getting traffic from old bookmarks and mistyped URLs. Meta was counting 404 page hits as lead conversions and optimizing for people most likely to hit broken URLs.

What we did

1. Cross-referenced Meta lead event volume (180/mo) against CRM entries (40/mo) — 78% discrepancy
2. Pulled pixel event log and traced all Lead events by URL — found 140/mo firing on /old-contact.html which returned a 404
3. Deleted the old pixel trigger, migrated all lead tracking to CAPI via server-side webhook triggered on CRM record creation only
4. Rebuilt Meta campaign from scratch — new conversion event, new learning phase based on real lead signal

Why it worked

Meta's algorithm is brilliant at finding more of whatever you tell it to optimize for. When you accidentally tell it to optimize for 404 page visits, it finds more people likely to mistype URLs. The server-side CAPI approach solves this class of problem entirely — lead events only fire when a real record is created in the CRM, making ghost conversions structurally impossible.