The last few times I've tried to install Windows on things, it was actually surprisingly horrible. The problem is, the generic install media has basically no drivers on it, so you have to go fetch it all manually, from all the respective manufacturers' web sites. It is, of course, fairly hard to download your network driver without a network driver, so you'd better have another computer and some USB storage around. Also, many of the drivers come only in the form of installer bundles that are themselves hundreds of megabytes and full of crapware.

In comparison, installing Ubuntu is a breeze, almost all the drivers you need are included with the install media and installed automatically, etc. Unless you have brand new, just-released hardware, it "just works", and even with brand new hardware there tend to be guides on the internet that are still easier than getting drivers installed on Windows.

Actual thing that happened: My mom said she needed to reformat an old laptop but didn't have the Windows media and wondered what to do. On a lark I suggested installing Ubuntu. A few weeks later, having not heard anything, I asked what happened to the laptop. She said she installed Ubuntu and it worked great. Never asked me a single question.