I think my biggest flaw is lack of originality. My ideas are usually inspired by other people's ideas, or I recycle my own storylines. I don't have many ideas that I think are really creative and original.
I think I'm also overly ambitious. I tend to bite off more than I can chew, either with too many stories going at once or too much going on in one story. My projects always seem to take years to finish, either because the stories are just really long or because I only write on them once in a blue moon. I used to be a writer who wrote one story at a time and finished each one in about a month, but that was a long, long time ago. I kind of wish I could still be that way without sacrificing the quality of my writing.