And of course, we're all talking about how to communicate to readers what's in the book. And as Manus points out, you're also trying to entice readers. Manus writes:
What are readers getting excited about? Seriously, make a list of the buzzwords. Readers who liked those popular titles will be looking for similar titles to enjoy. To help them find yours, focus your book description on what the readers are actually looking for.
She's not talking about lying to people about what's in your book--that's going to backfire, badly. She's talking about figuring out how people who love books with X, Y, and Z in them figure out whether or not a book has X, Y, and Z. If your book also has A, some B, C, D, something between H and I, Q, T, and a little W, don't highlight that--it's too complicated for a description. Keep it simple: If you like X, Y, and Z, read this book.
In other words, you are designing a signal. You are creating a code.
When readers talk back, they also talk in code. Even if they don't know it.
"Not much happens" was a HUGE screaming signal that I had incorrectly positioned Trang as adventure sci-fi. It was not subtle to me, because I have heard many, many jokes made about people who don't like [INSERT CLASSIC OF ENGLISH LITERATURE HERE] because "nothing happens"--it's right up there with "Shakespeare uses too many big words" among Responses That Will Instantly Evoke Scorn Among the Literati. And it means something specific: It means that the reader likes plot and doesn't care about characters or prose.
I was lucky that that response was so stereotypical. I was also lucky that I have almost 20 years of making a living as a writer to give me confidence in my writing. I don't read something like that and think, "I have failed" or "I'm a bad writer." I read that and go, Oops! Better change the cover!
I think if that kind of review is going to make you extremely upset, insecure in your abilities, and (most important) like you don't want to write any more, and if you can't possibly control that response, then I guess you probably should refrain from reading reviews. But if you can take a step back, disconnect your emotions and your self-esteem from what is written, and read reviews for the feedback they contain about what readers were expecting and what they got, they can be very helpful.
Even when I receive positive reviews, I don't think to myself, Gee, I guess that means I can write! Of course I like getting those sorts of reviews--I'm not made of stone--but if I couldn't write, I would have starved to death back in 1992. What those types of reviews tell me is that 1. Trang is positioned correctly, 2. it will work as a loss leader, and 3. I better get Trust out, because people are waiting for it. That is all very useful and motivating information to have, but it doesn't change my opinion of my book or of myself as a writer.
I think the important thing to remember when communicating with readers is that there's no such thing as an empirically good book. It simply doesn't exist. I know someone who likes only political nonfiction, I know someone who likes only lesbian erotica, I know someone who likes only classical Greek and Latin literature. You could never, ever get those three people to agree on whether a particular book is good--it's just impossible. And you don't have to--you just have to make sure that your book on health-care policy, your story about nude cheerleaders who spank, and your translation of Euripides all wind up in the right hands.