Very interesting point made out by this blog post by Patrick Rhone, about how Microsoft's core business faces an existential threat:
Microsoft for many years had convinced the world that, in order to get “real work” done, you needed Office. … Then, she explained, the iPhone came. There was no Office. People got things done. Then the iPad came. There was no Office. People got things done. Android came. People got things done. All of those things that they, just a couple of years ago, were convinced they needed Office to do. They got them done without it. And thus, the truth was revealed. … Like the curtain finally falling from the Wizard of Oz to find just a small, frail, man pretending to be far more powerful and relevant than he really was. Microsoft’s biggest miss was allowing the world to finally see the truth behind the big lie — they were not needed to get real work done. Or anything done, really.
And that will be what ultimately kills them. …