For me its a bit different because I write iteratively. By that I mean, I write some, I edit some, then write some more, then edit some more, then writes some more, then edit some more... and so on. And by edit I mean the full spectrum. For example, on my last pass through my current work I dropped an entire sub plot(along with some characters), added some material, and rearranged some chapters. A prior pass I removed 15k words worth of materiel (about 50%). So by the time I reach "the end" of my book, I have already accomplished around 90% of the editing I can do.
After that I pass it to my wife who will do 3-4 pass through the book (she does a pass, then I review, then she does a pass, etc).
Once that is done, I pass it to my professional editor. Then I do what she tells me to do. After that I do one last pass to make sure nothing got lost in translation, and usually put a bow on it and call it done.
Is it really done? Probably not, but at some point you say "time to write book five!" and move on. Someone once said "books are never completed, they are abandoned" and there is some truth in that I think.