Microsoft Windows
The past two laptops I’ve owned, I’ve kept Microsoft Windows installed in it, but I almost never use it. The only time I ever use Windows is to load a product upgrade or run a driver that isn’t working properly in Linux. Like for example, right now I am booted into Windows to read and reformat a memory card that Linux is refusing to see at all because it is corrupted. It seems to work okay.
Every time I’ve loaded Microsoft Windows, I’ve always noticed how truly slow the operating system is compared to the striped down version of Linux I run with the XFCE Window Manager. It also is trying to sell me some kind of new product, that is always free and easily installed in Linux like office software, software updates, and virus protection. Why pay for something that is already free and easier to install?
I agree that some hardware and software requires a bit more fiddling to get working perfectly. But on the other hand, not all Windows programs are easy to install, especially if you have to buy them, download them and run them through an installer — compared with the ease of apt-get. Linux’s powerful command line makes scripting, and basic repetitive tasks much easer to do then doing a lot of clicking. But for more complicated tasks, there are almost always easy to use GUI programs like OpenOffice and QGIS.