There are a few things you can do in Windows, which can't be done in Linux, and that's why I haven't completely got rid of Windows. To name two occasions from my experience, Visual Studio and several games which aren't available in any Linux distro. Judging by the history of pooya's posts, he's used to writing C#, which is more or less a Microsoft product as it runs in the .NET framework, so that could be it.

But the reason most people struggle to migrate is habit. If you're used to Microsoft products, then the switch will be uncomfortable at first.