If your site is utilising a framework like React, you are likely running a single-page application aka an SPA . In basic terms, a normal website will reload the page each time you click on an internal link to visit another page. When you do this, scripts and trackers like Microsoft Ads’ UET snippet are reloaded. They then capture the newly loaded page and send that information back to the platform so you can use it to build custom audiences and goals. This is the same for most pixels.