It's a handy way of ensuring that your time spent dicking about is minimized. I used nothing but Windows from 1999 until mid-2010 (and I used MS-DOS as well between 1993 and 1999). Windows 3.x was horrid, Windows '9x was horrid, and Windows 2000 and following have their disadvantages, but there's a lot to be said for never having to relearn any of the basics. I used only Windows XP from 2002 (or 2003?) until 2010, which made things even more convenient.
Some people seem to like shaking things up every few years, but I'm not one of them - it just takes time away from doing what I consider more interesting stuff.
That's certainly not my experience. After some trial-and-error during the first couple of months, in which I move from Gnome → XFCE → Fluxbox → Awesome and I configured the system to my liking, it's been extremely stable. Four years and two laptops later, I'm using the same setup without having to do anything but the occasional update, and the fact that I'm on a rolling release (Debian Sid) means my software rarely changes a lot at once.
Same here. A person who knows how to program and who are easily annoyed by things like inconsistent computer behavior or lack of design aesthetics should probably avoid Linux if their interest in an OS is to help them be productive.
I find Linux to be extremely consistent; almost all programs I use read data from stdin, process it according to some arguments and output the result to stdout ;)
A lot of Linux based devs prefer "classic" development tools like emacs or vi and operate primarily from the terminal.
These things tend to stay very consistent over time, if I was using Windows I would have had to learn powershell over the last few years. My BASH knowledge is still as applicable as it was 10 years ago.
Some people seem to like shaking things up every few years, but I'm not one of them - it just takes time away from doing what I consider more interesting stuff.