Why Tracking Breaks

Tracking is fragile because it depends on the browser cooperating. Knowing the common failure modes helps you debug fast and build more robustly.

The usual suspects

• Ad and tracking blockers that stop vendor requests entirely.
• Browser privacy features (ITP, ETP) that shorten or clear cookies.
• Consent denial, so tags hold or run cookieless.
• Single-page apps that change the URL without a real page load.
• Tags firing before the data they need exists (race conditions).

The resilient answers are the ones from the privacy material: server-side tagging, first-party data, robust triggers (History Change for SPAs), and firing on confirmed events rather than fragile page loads.