It's inertia, at least in my own experience. I've had a bunch of things I've been meaning to do but was lazy and stuck in my habits until some new event made me say "enough is enough" and then I try the new thing and a lot of the time I end up thinking I should have just done that sooner. But before that, it's "I know there's problems with this but it's what I know".

Doing the jump to Linux is the current one I'm procrastinating on. I use it already, just not on my main machine, so it's not even like I don't know how it is. I've just had a Windows main machine all my life and installing a new OS is a pain. But I do want to feel amusement instead of annoyance when hearing about the latest BS MS is trying to push.