People, I dunno. There is term in language learning courses "falser beginner". I doubt all these people who start learning languages and stop are bipolar.

How many people dropped out of school when pregant or get a career gig, saying they will finish and never do?

How many people change few jobs, drop out of few schools before finding what is right for them?

Let me tell you... quite a lot.

Normal people do this too. I think we sometimes like to blame our BP (or put them in context of the "illness").

I guess it is partly condition of human being trapped in other things to do.

(and yeah, I never got my Prague guide licence although I paid bloody money for the course... and I doubt I ever will now).