Google announced its mobile-first index in November 2016 because they were trying to solve a problem.
Most people were using Google on their mobile devices, but Google’s ranking systems were based around the desktop.
The solution — mobile-first indexing — changed the world. We’re never going back to the days of optimizing search for desktop only.
3 out of every 5 searches happen on mobile, and mobile far outpaces desktop as the number one method of searching.
That datapoint in itself is reason enough to move to a mobile-first indexing approach.
But there’s more. It used to be that mobile searches happened by people, out and about, on the go, away from home.
Not anymore. A full 77% of mobile searches now happen at home or work.