Because we still have/need PC's. Mobile is a new market, a new branch of computing, so naturally there is going to be a lot of growth there. A lot of people do

Because we still have/need PC's. Mobile is a new market, a new branch of computing, so naturally there is going to be a lot of growth there. A lot of people don't need a full-blown PC at home, so a phone that lets them check facebook and read articles covers most of their needs. And as you mentioned with india: computers were simply not affordable for most, but smartphones are. But again, this is just growth potential and untapped markets. Businesses will still use computers, as will gamers, developers, writers, filmmakers, accountants... and so on. Mobile has helped them, but it hasn't obsoleted PC's. We still need them to create the things to be consumed on mobile devices.