Are you able to write fast and well at the same time?
As a recovering perfectionist, I've had to give up toiling over every line of prose, making each of my sentences as perfect as can be before moving on to the next. For one thing, it used to take me forever to finish a story, and for another, it's easy to lose sight of the big picture when you're focused on minutia such as word choice and sentence fluency. The first draft isn't the place for any of that.
It's the place for vomit.
I'm learning to hurl my first drafts onto the screen and clean them up later. It's taken a while, but I'm finally getting to the point where I don't care as much that my early sentences are clunky, my descriptions are sadly lacking, and nothing is even close to perfection.
Do I share my first drafts with anybody? Heck no. I have enough trouble reading them myself without cringing, wincing, and groaning at how horrible they are. But they're there. You know what I mean? By the time I finish, I have a complete story with a beginning, middle, and end. And that's when I have something I can really work with.
I'm about halfway through the first draft of my Captain Quasar novel, and I'm striving to keep the momentum going strong. Is it beautifully written? Nope. Are there incredible descriptions, breathtaking action sequences, and plenty of witty banter? Not yet.
But there will be. Once I finish this rough cut, I'll be spending lots of quality time with the captain, polishing up his novel-length misadventure and beating it into submission-worthy prose.
Somebody wise once said, "The worst stuff you write is better than the best stuff you don't."
In other words: just puke it.