For aspiring writers, both beginners and those at more professional levels, you really can’t overdo it on the feedback. Julie Wilson at the Book Madam & Associates blogs makes that point in an excellent way, by asking several authors what they do to get their manuscript absolutely polished and ready to submit.
Pretty universally, the answer is to have the book read and critiqued as much as possible, before it ever gets to an editor or publisher. That means everyone from your spouse to your best friend to your writer’s group to your agent — whoever is willing to give you an honest critique.
This is a frightening prospect, of course. This is your baby, and you’re bound to get many suggestions for changes. Your writerly pride will get wounded, and after a while you may be tempted to feel like the book isn’t worth anything at all. But don’t despair. The purpose of all of this is not to make you feel worthless, but simply to show you a few blind spots, and find ways to improve both your writing and this particular story.
Remember that if you’re trying to publish, then you’re not just writing for yourself; you’re writing for an audience. And these initial readers are that audience. Some might be reading with a more critical eye than others, but if they find a glaring contradiction, or several of the readers get “stuck” on the same chapter, that means there’s really something there. And if they see problems, then your “real” readers — the ones you want to buy the book — will also see them. If you can rid of problem areas before re trying to sell the book to those readers, they’ll be much more likely to buy.
The other side of the coin is that you don’t have to make every change suggested by everyone. Sometimes critics want to turn a book into something they would have written, instead of something you wrote. If you sense your book’s entire theme or plot changing into something that isn’t yours at all, that’s a signal that many of those changes aren’t really necessary. You remain the final judge.
But be open and listen to all the suggestions before taking some of them to heart or rejecting others. And leave as much time as possible between hearing their suggestions and deciding what to do about them. That will give you time to get over the initial shock and feeling of being “attacked,” and you’ll be much more able to assess the suggestions objectively.
Get all the feedback you can, and it will help you become a better writer, and produce better books.