If I have a tag manager, or all of my tags load after the page’s content has loaded, do I still need to use Evidon?
1. Not all tags can be loaded asynchronously – For example, ad serving tags that don’t render (load) properly into frames, such as an interstitial (or full screen) ads. Or, A/B testing tags, which allow for the comparison of two different versions of a user experience, can cause “flickering” (when the original page content is visible for a short amount of time before the testing script changes it) if loaded asynchronously.
2. Not all tags can be loaded after the onload event (when much of the page content has loaded) – For example, performance optimization tags leveraged to measure the entire page load and necessitate firing at the top of the page (to capture the full page load’s worth of data). Or, tag management technologies, leveraged to control the firing (or not) of most other 3rd-party tags on the page, can’t be loaded after the onload event.
3. Page fully rendered, or “document complete,” is still the most widely used metric for measurement of site performance by businesses; it’s important to note that this metric includes images, as well as JS files, which are timed to start rendering after the on-load event, or “time to interaction.” Because of how closely this metric is still monitored, it’s important to be fully aware of those resources loading after the on-load event.
4. You can observe the impact that slow tags, which load after the on-load event, have on the user experience by using the Ghostery browser extension. The continual loading of tracking technologies, even though the page appears to be able to be interacted with, still makes for a poor user experience.
5. Two last items of note – if you are deploying a tag on your site, doesn’t it make sense to ensure that the tag is achieving what it is supposed to achieve? Excusing slow tags because they load after the page content has loaded is the same as letting someone live in your house, but only choosing to pay rent some of the days. Additionally, more tags means higher risks of data leakage and security issues, no matter where they load on the page.