Full Answer

Facebook conversion problems trace back to four layers. Tracking failures are most common and least visible. If Meta Pixel is being blocked by ad blockers (31.5% of users), Safari ITP is capping fbclid cookies at 24 hours, or iOS 14.5+ users have opted out of ATT, Meta is optimizing with 30–40% less signal than you think. The algorithm builds lookalike audiences from the buyers it can see — if it's only seeing half your buyers, your targeting drifts.

CAPI gap: Meta Pixel + CAPI together is the current gold standard. CAPI recovers the conversions Pixel misses. Without CAPI, EMQ (Event Match Quality) is lower, attribution is weaker, and the algorithm can't match as many of your buyers to Facebook profiles.

Audience-creative mismatch: When tracking is broken, targeting degrades over time — Meta stops finding your best customers because it doesn't know who they are. This looks like a creative problem but is actually a data problem.

Structure: Learning Limited ad sets, too many ad sets fragmenting conversion volume, and frequent edits all prevent Meta's algorithm from stabilizing.