For me, there are two stages to critiquing: - The first, learning-the-craft stage. For me that means that I give something out (one or two scenes, maybe as much as 10k at most), that I can learn what NOT to do. Obviously I believe when I give something out that it is as good as I can make it, but I am still learning. If many critiquers tell me that something in my style is not right then I'd rather learn about it sooner than later, so that I can correct my style before I have written the whole damn thing. - When I have written the whole thing, much later, than I will give it out in its entirety for a 'proper' critique, Alpha and Beta. But this is a whole different thing, for me. Disclaimer, this is just my very personal approach.
Critique of the whole can be a problem. It usually means that you would need to practice more on your writing style, but most works are posted for grammar check and feedback.
I always itch to get a critique when I finish a draft. But what I really want is to find out what I did right, not what I did wrong. (Does anyone ever wanna know what they did wrong? ) It's hard to get that across to a reader (not that it's going to help the overall process). The needy kid in me screams, "You're supposed to read the good stuff and skip over the bad," but they never do. I guess that's a good thing, though... right? During the course of writing Aliens DBATK, twice I thought it was finished and ready for market. With great glee in my heart, I sent it out to readers and turned my mind to other stories while eagerly awaiting glowing feedback, pronouncements that I've written the best novel of all time, etc., etc. But, alas, the feedback was always more in line with reality than any fantasy I'd lost myself in. I guess that's a good thing, too. And now, writing the 8th draft, I have to wonder if I won't end up going through that yet again. Will this draft finally nail down all the loose ends, push the plot into an exalted state of grace and rid me of the scourge purple prose hath placed upon me? I don't know. I may end up doing a 9th or a 10th draft because, once again, I've fooled myself into thinking I have written The Great Novel. I may still be rewriting this damned thing on my deathbed, but I refuse to stop until someone says, "Okay. It all works."