In my opinion, there are a lot of valid reasons to switch to Linux.
Mine was simply curiosity and boredom with Windows, I like the fact that I can configure everything and I do not mind the time involved - for me my computer is as much a hobby as it is a workstation.
I have gone from Debian to Ubuntu to Arch Linux and from Gnome to KDE to Xfce to Awesome and every time I had fun setting everything up just right.
No that I got everything like I want it, I also noticed that everything is much, much more comfortable than windows.
From the obvious speed boost to easier software installation, from workspaces to a tiling window manager...
And now that I've gotten used to it, I feel that the terminal is actually superior compared to mouse driven GUIs for most things.
I like to work efficiently, and once you got the necessary practice the keyboard just trumps the mouse.
Of course all of the benefits above take a lot of time to get to - practice and simple set-up time.
Not everybody can or wants to put that time into their computer system.
But you don't have to.
Not every distribution is Arch Linux/Gentoo/LFS.
Ubuntu or Linux Mint do most of the stuff for you and still offer a lot of the niceties of Linux - Package Managers, Workspaces etc.
Recently a lot of my friends had to start installing Linux too because they needed it for their University courses and none needed more than an hour of introductionary time to get the basic hang of it.
Of course one of the main problems is that the most big, propietary software suits and games do not have Linux ports.
Yes, Wine and VMs can alleviate that, but not a lot of people (me included) want to spend 3 hours to get a buggy version of a program working.
Don't get me wrong, lots of software runs great with Wine, but some just doesn't and that's where the problem lies.
But all of that is not an inherent advantage of Windows and if that is your only reason to stay, maybe try some dual booting.
Oh, and just a short note about the people complaining about there being too many distributions: How is that a problem? Just think of it as seperate Operating Systems if you must.
Most people probably don't even notice the differences between distributions on a lower level, just the different default Desktop Environments they use and how big their package repositories are.