Most answers offer a triple-A game dev perspective, so here's some indie... Toolsets are much more obtainable on Windows. That includes cracked apps, education

Most answers offer a triple-A game dev perspective, so here's some indie... Toolsets are much more obtainable on Windows. That includes cracked apps, educational licenses, and plenty more sources. They're also more expansive; almost anything runs on Windows, even if in an intermediary way. There is also a vast majority of apps that run solely on Windows. Huge majority of your end users are on it, so you need to have it anyway. Running a VM just to test stuff out is inconvenience to say the least. Other devs to whom you communicate use it. Documentation and help all over the internet covers Windows side much better than other OS'. Source files already available for inspection are usually made to compile on Windows. Macs are expensive and whole experience of being jailed in OSX doesn't really go well with indie attitude. IOS gold rushes somewhat turned game dev eyes on it, but that's dying recently, as more and more devs try to find opportunities on various existing and upcoming Android stores. Toolsets for iOS sucked anyways. Linux (on which I'm trying really hard to develop a workflow) lacks application ecosystem neccesary to fuel all the game development aspects. Last, but not least - gaming. We game a lot. And a lot of it is nostalgic, some for inspiration. No other OS offers such a huge quality game title offering as Windows does.