Full Answer

The question matters because most WooCommerce stores operate with incomplete data, and incomplete data produces incomplete answers. Zero-party data does not replace performance marketing — it supercharges it. Ad campaigns still drive traffic, but zero-party preference data ensures that traffic converts better, retains longer, and generates higher lifetime value. It is the intelligence layer that makes every other marketing investment more effective, without depending on any tracking mechanism that browsers or regulators can block. That's the surface-level picture — the deeper issue is structural.

WooCommerce's default analytics stack runs entirely client-side, which means every measurement depends on a browser loading a JavaScript tag without interference. Ad blockers, Safari ITP, consent rejection, and in-app browsers each suppress a portion of those tags independently, and the suppression rates compound. A store losing 15% to ad blockers, 10% to ITP, and 20% to consent rejection isn't losing 45% — some overlap — but the real loss is still 30–40% of events that never reach the analytics platform.

Server-side event tracking captures these events at the server before they ever touch a browser, which means the data survives every client-side suppression mechanism. The conversion count becomes reliable, the attribution chain stays intact, and the store owner gets a measurement foundation solid enough to actually optimise against ([server-side tracking for WordPress](https://seresa.io/blog/server-side-tracking-wordpress/)).