...or whatever they are calling it these days.
I see authors on this site, and some excellent authors on other sites, who seem unable to focus on a story long enough to see it to completion. They will write a few chapters of a new story, then ignore it and go haring off in a new direction with a different story - again to write half a story only to once again drop it and start something else, or go back and add a chapter or two to one of their previous efforts. They end up with a large body of work, but most of it a work in progress and little of it completed.
Does ADD or ADHD affect writers more than it does the general population? This drives me nuts.
note: I'm not talking about incomplete/inactive stories - especially where the author has passed away or stopped for whatever reason. I'm talking about writers who have a fairly steady output - just not focused very well.