The illusion of the Google Speed Test
Page speed (the time it takes for a page to load) is one of the most important SEO metrics today. In other words, faster pages get more traffic from Google. For this reason, website developers are constantly testing their pages with Google's Speed Tester tool (https://pagespeed.web.dev/) and trying to improve poor loading times. The problem is that the PageSpeed test is only a simulation tool that does not match the metrics of Google or Bing. Google measures in real time through the Chrome browser.
While it is possible to get top results in the PageSpeed test by using tricks, in reality these tricks are not recognized by Google. So the website owner thinks he has a page that is classified as "fast", while Google classifies the page as "slow". The most commonly used trick is loading delay using the cookie banner: the page loads only after the user clicks on the cookie banner (accept or reject). This loading delay is not registered by the SpeedTest tool, the test is successfully aborted after a few seconds and the page receives the best possible test result. In reality, however, Google continuously measures the page load time throughout the navigation process in the Chrome browser.