After many GA4 audits, the same issues come up again and again. Here are the top 10 — ranked by how often we find them and how much they distort reporting.
1. Internal traffic not excluded
Office IPs, dev environments, and your own team's traffic showing up as "users". Easy fix: Admin → Data Filters.
2. Cross-domain tracking missing
Sessions break between www → checkout subdomain. Conversions attributed to "direct" instead of original campaign.
3. Conversion events not marked
Events fire correctly but never marked as conversions in Admin. Reports show no goals.
4. Purchase event missing tax/shipping
Reported revenue 15–20% lower than backend. Value field excludes tax and shipping.
5. No custom dimensions
Cannot segment by plan tier, user type, content category. Reports useless beyond traffic-level views.
6. Enhanced Measurement misconfigured
Defaults firing duplicate events on SPAs. Or scroll tracking sending too much noise.
7. BigQuery export not enabled
Free tier of GA4 includes BigQuery export. Most clients don't enable it. Once gone, that data is gone.
8. Google Ads not linked
Conversions don't import to Ads. Smart bidding can't optimize. Ads → Tools → Linked Accounts → connect.
9. User-ID not implemented
Cross-device tracking missing for logged-in users. Drop-off and cohort analysis broken.
10. Data retention at default 2 months
GA4 data retention defaults to 2 months. Should be 14 months on free tier. Audit + month-over-month reporting impossible at default.
