If there was one more thing that users might have hated more than the Start Screen it was the idea of full-size apps. I’d say when Microsoft originally said it planned for all apps downloaded from the Windows Store to run in full screen or snapped to a small area to the side, users were open to the idea if they only opened one app at a time anyway. Very quickly this turned into an outright disaster though.
First Microsoft only allowed for limited multitasking with these full-screen apps. As such, trying to type in one app while reading in another ways a royal pain. Eventually, Microsoft made it so users could split their screen between apps, which still wasn’t enough for desktop and notebook users.
In Windows 10, Microsoft is going back to what works. Windows Store apps now run in the Desktop just like other apps. Tablet users still get the full-screen treatment though.