The first time Windows users started looking for an alternative OS en masse it was 2012, and Microsoft had just released a desktop UI so bad it would be almost entirely purged from existence within just three years. Windows 8 was all about big, square icons designed for a new wave of touchscreen-enabled laptops and Windows phones. The classic desktop designed for mouse and keyboard was gone, based on a prediction that soon everyone would want to use all their devices in the same way (this has still not come to pass).
At the same time Microsoft's UI designers performed an all-time beefing-it maneuver, its business geniuses rolled out a new Apple-inspired Microsoft Store and method of locking down apps that spurred Valve's Gabe Newell to declare "Windows 8 is a catastrophe for everyone in the PC space" and start investing into Linux development.
