Today, everyone has smartphones with them, constantly communicating and looking for information. In many countries, the number of smartphones has surpassed the number of personal computers; having a mobile-friendly website has become a critical part of having an online presence. In the US alone 94% of people with smartphones search for local information on their phones.
The desktop version of a site might be difficult to view and use on a mobile device. Interestingly, 77% of mobile searches occur at home or at work, places where desktop computers are likely to be present. However using this mobile access the desktop version requires the user to pinch or zoom in order to read the content. Users find this a frustrating experience and are likely to abandon the site. Alternatively, a mobile-friendly version of your website is readable and immediately usable.
The majority of users coming to your site are likely to be using a mobile device. Mobile is critical to your business and will continue to be so – whether you’re blogging about your favorite sports team, working on the website for your community theater, or selling products to potential clients. Make sure visitors can have a good experience on your site when they’re visiting from their mobile devices!
Reference: https://developers.google.com/search/mobile-sites/