I have difficulty finishing what I've started. I'm also a complete dilettante, which feeds back on difficulties in finishing things. I make short films, photograph, draw, write, compose music, but all really half-assed. In fact, most of my short films ended up being 'trailers' for what I really wanted to make.
I found, though, that if I combine things, I can bluff my way to a step above crap.
At one point, there were probably fifty or sixty unfinished short stories in a folder on my computer, all written over a period of about three years. eventually, they did get finished, but in a different way; two years writing a 300-page (single-spaced), five-act play that brought together all the characters (who totaled over 120) and plots from the short stories and collectively resolved them.
"And then they were all hit by buses!" ... That's not how it really ended, but it might as well have been.
So, that's the personal flaw: resolution issues.