The next time you're waiting in line for anything, take a look around. How many faces do you see buried in their smart-phones? Are you doing that now yourself? The alarming fact is, PC sales are dying while mobile phone sales, tablets and apps are exploding. But search engines on mobile phones are starting to penalize websites that take are not optimized for mobile.
Try loading your website on your phone. If it takes more than 3 seconds, and if you have to pinch-and-increase to read any words, it's most likely that over 95% of your mobile patients abandon your website. Considering that almost 50% of your traffic is now likely from mobile - that's a giant hole that needs to be plugged. Search engines are promoting websites that load quickly on mobile phones in search results.
It's becoming a mobile dominated world. Smart practices recognize this as an opportunity, not an annoyance.