That's the truth. Sometimes life gets in the way of finishing your personal projects.
My first rush of fan fic was about seven years ago and my last project from that batch will likely never be finished. It was a Gargoyles series set in the past for which I'd done quite a bit of research and I had a detailed timeline worked out -- then my hardrive went kaput and I lost all my research, story notes, and works in progress. I have copies of all my finished stuff because it was posted to an archive (not AFF). But I just don't have the heart to try to recreate all the data that was lost.
Aside from misfortunes like that, I have a full time job. I also have a disabled husband, two children, one of which has a chronic medical condition, the other is in diapers. We both have aging parents. Sometimes things like my fan fics have to be put on the back burner.
And sometimes you start a piece and lose enthusiasm for it after a while. Especially if you are forced to take a break from writing. I have a problem that when I get about 3/4 through a long piece, I suddenly become unmotivated. I think it's because once I get to the point where I see how it ends, I just don't feel as much of an urge to write it down for others. After that it's a matter of self discipline to get the thing finished.
Then again, sometimes I start a piece and partway through decide that it probably only interests me and isn't worthy of being posted. So there's no reason to finish it anyway. At least to me.