I think, if you want to improve yourself and you aren't hurting other people by doing it, any reason that motivates you is a good reason

Because, in the end, you come out a wiser person, no matter how or why it happened.
I took 2 years of Mandarin Chinese in college because a girl I had a crush on randomly asked one day if I would sign up for courses with her. Nothing ever happened with the girl, but now I have 2 years of Chinese under my belt, enough to recognize simple sentences and read some traditional and simplified Chinese (since I haven't been keeping up in it). In dabbling with Japanese, I can also reason out what some kanji mean.