Too Long; Didn't Read
Aditya-dwivedi explains how you can measure page load time with Selenium for automated browser testing. Site speed is the amount of time it takes for the content/page to appear on the screen. Slow page speed means that the search engine crawler can crawl less number of pages within the allocated crawl budget, which would eventually show up in the rankings. Lower the page-load time, the better is the usability factor of the product, better is your conversion rate.