How long do you wait for a web site to load? Not long I bet, waiting for something is frustrating and people do not like doing it. In a world where information is almost instant our patience has grown less and less and so speed is part of the usability of a website and so the faster a website the better the usability.
How fast is fast?
In Google’s Site Performance for Webmasters video, Maile Ohye, states that:
2 seconds is the threshold for e-commerce website acceptability. At Google, we aim for under a half second.”
Half a second is literally the blink of an eye. Google already considers page speed a ranking factor, meaning that sites that load faster would rank higher than similar sites that load slower.
On the 4th November 2016 Google announced that it is in fact looking to move to a ‘mobile first’ index in 2017, with their algorithms eventually primarily using the mobile version of a sites content to rank the pages on that website.
Although our search index will continue to be a single index of websites and apps, our algorithms will eventually primarily use the mobile version of a site’s content to rank pages from that site, to understand structured data, and to show snippets from those pages in our results. ~ Google https://webmasters.googleblog.com/2016/11/mobile-first-indexing.html
A fast site is good user experience and a good user experience will lead to higher conversions and now that Google is pushing hard in the direction of user experience, it’s really a no-brainer, websites need to be fast to succeed, and with Google switching to a mobile-first index, websites need to be fast not only on mobiles, but on all devices.