From the Business Insider: Flaw in Micosoft's strategy. Microsoft's strategy for Windows 10 hinges on what it calls "Universal Windows Apps", or "it runs the same on every platform". Issues: 1) developers have no real reason to build Universal Windows Apps. 2) legacy apps run just fine, so why reinvent just for mobile devices? 3) lack of win/10 adoption (so far) 4) lack of Windows Phone market share 5) existing successful mobile apps were never deployed on desktops, so migration is not an incitement. 6) the Universal App has restrictive APIs 7) the coup de gras; many successful applications are agnostic to the Windows PC. See the original article for details here.