Google will take you sites loading time into account when ranking your website.
So you want to make it as fast as possible.
If you use Google Analytics and maybe also Google Adsense, then they might be a big factor why your site is loading slowly.
With a pretty small code snippet you can increase the loading time with GP4.
It might be a bit hard for some people to set this up if you’re not a savvy user that are OK with getting dirty with file-editing and messing with the code.