If your website was designed on a desktop and merely shrinks on a phone, you are losing customers. The majority of web traffic now arrives on mobile devices.
Design for the Smallest Screen First
Building for mobile first forces you to prioritize the essentials. When your phone experience is excellent, your desktop experience follows naturally.
Shrink Tap Targets and Text
Buttons need to be big enough to tap reliably, and text must be readable without zooming. Small annoyances add up to abandoned carts and lost leads.
Mobile Is a Ranking Factor
Google crawls and ranks the mobile version of your site by default. If mobile is an afterthought, your whole site suffers in search results.