No one likes slow page loads including Google. Now that Google takes speed into consideration when ranking sites, your load times can also influence how easily users can find you in the first place.

This means that it’s in Google’s best interest to cater its search results to mobile users. They don’t want to direct their users to sites that won’t load or function well on their devices.

As a result, mobile user experience will now play a major role in search rankings — even in desktop search results.
User experience has long been a factor in rankings, but prior to this shift, it only took desktop experience into consideration. So even if a site provided a poor mobile experience, it still had a shot at ranking on page one.