I have used Windows ever since I learnt to use a PC, and I would count myself as above-average, in terms of ability (have done a little bit of programming, can solve most problems myself, or at worst have to do a quick Google search). I want to like Linux, but I find that Windows is easier to use in one significant way, and it is this reason that deters me from using a Linux OS as my primary. I think there may be many other Windows users like me.
OK, I am used to very, very occasionally reverting to the old DOS command prompt when I need to muck about with a hard drive and the standard Windows Disk Management won't cut it. But apart from that, everything I need to do has a nice, clear GUI, and accompanying instructions telling me what to do. Last time I tried Linux again, it was Linux Mint LXDE, and so far I like it best, of the distros I've tried. It's quick, looks good, doesn't hog resources, and has a small install footprint. But I wanted to carry out the simple task of increasing the double-click sensitivity of the touchpad. I must've spent three hours in all, perhaps longer, trawling forums, trying out suggestions to give myself admin privileges, then make this new file, open Terminal, type this, move this file here, etc, and only the last suggestion worked. In Windows, I simply do Control Panel > Mouse > Double-Click Speed, all within GUIs. Yes, I know Synaptics makes its own device driver for Windows, which it doesn't for Linux, and this is not the fault of any Linux developers, but I'm just telling it like it is: no-one wants to spend ages trying to get their system to a basic usable state, when they could make a few quick clicks. This is one example that is highly typical of my general experiences with Linux.
I do not, like some new Linux users, expect to be handed anything on a plate: it's free, after all, and most of the people who work on it do so out of generosity towards others who use computers. And I don't think I need to explain to you the many advantages that Linux OSs have over Windows. But until Linux is as easy to use as Windows XP (what I'm on at the moment), I'll be sticking with it as long as it's supported!