Of course, what I should have made clear in my last post was that I was referring to the First Draft. And Phil and Tracy, you are absolutely right, it is just the beginning. But at least finishing the first draft is the End of the Beginning even if it isn't the Beginning of the End.
I know the veracity of this only too well. I am currently still editing/revising my first WIP which has to date taken up a fair chunk of the last two years. I'm starting to get heartily sick of it now and am determined to knock it into some final shape before much longer so I can start submitting. Although I want to be done with it I find it impossible to stop tinkering even with the bits I'm reasonably confident about. If it ever should make it into print I could well be sneaking into Waterstones with a bottle of Tippex to make a few "last minute adjustments".
It's very easy to get addicted to editing. A lot of writers complain about it, but I've come to love it. In some ways I do think it's the most creative part; adding colour, improving dialogue, cutting and embellishing. But I also recognize a tendency to obsess about it, and therein lies madness. Some writers I know try to perfect each chapter before moving on to the next one. There is a real danger they will never finish the book because it will never be good enough. I'd rather get the first draft down, warts and all, before worrying about how crap it is.