Probably because of the name Windows - people had high expectations of it, which it did not deliver for obvious reasons - you want 'real' Windows, you go with W

Probably because of the name Windows - people had high expectations of it, which it did not deliver for obvious reasons - you want 'real' Windows, you go with Windows 8. Also, ChromeOS is cloud based (good luck using it offline, lol) and easy to manage centrally, while RT is basically Android for tablets.