I've been using some Linux flavor for about 15 years. The biggest thing about switching (at least back then) was I knew how to configure Windows just to my liking. With Linux it was a lot more difficult because I had to google everything. Like "how do I change the wallpaper?" How do I get the login screen to appear on the correct monitor, etc. It was just frustrating because I knew how to do this in Windows, but I felt like a major noob again with Linux.