It's a double-edged sword, isn't it? As a writer, I want people to read my work. I don't write for myself (I mean I do, in the general sense, but for me the purpose of any specific work is to be read). Knowing how real, actual readers respond to the work is invaluable. But at this stage, the work isn't perfected, at least as much as any finally released product will be. There's so much wrong with it, and it can be hard to show that to another person. What if they think I'm a bad writer forever? Not to mention that hearing harsh criticisms of something that has been the result of months, even years, of work can be difficult.
I have a pretty thick skin. I definitely fall more on the "all the feedback!" side of the spectrum. I want to know where my manuscript falls down. I need the perspective that I can never have as the author. I have no problem sending my manuscript out there to betas or others.
Then the first response comes in. Sure, there's a lot of problems they've found. But it starts to give me an idea of what I need to work on. The manuscript starts to feel fixable.
Then the second response comes in. And, wtf, it's completely different!
Everyone has different preferences in a story. Some people will identify with characters and some won't. The feedback can be all over the place. It can be enough to make the manuscript seem an irredeemable mess. If everyone finds a different problem, that means there are infinite problems!!
Okay, deep breath.
The great thing about readers is that they are all different. There is no universally beloved book—no, really, not a single one. Gathering a wide range of feedback is excellent, but a manuscript could be crippled by trying to cater to everyone one of them. Just got to take the advice that resonates, fix the unintentional mistakes, look for common issues. And remember: in the end, it's your book. Take what you can use from the feedback, but write the book you want to write!
This is for the guy whose name is an instant touchstone for "brilliant author." And not by some illiterate schmoe.
(PS, if anyone is interested in reading a YA fantasy or adult SF...)