It has come to my attention that a great many of you are still confused regarding the role readers (aka "amateur reviewers", "goodreads members", "booklikers", "gangster bully trolls") play in the life cycle of your book. So I've compiled a handy little list to help you remember all the things that readers are not:
Readers are consumers. We're your customers. Nothing more, nothing less. We owe you nothing, other than that we obtain your book legally.
"But, Three," I hear some of you protest, "if you aren't writing reviews to tell us how to improve, why do you point out all the grammar and spelling errors? The logic fails and inconsistent characterization? Surely that's so authors can improve, right?"
I can only speak for myself, but I give specifics so that other readers will know whether or not the things that bother me will also bother them-- and I suspect other reviewers provide details for similar reasons. Essentially: to back up our opinions.
Reviews that simply state the writing was horrible are useless to me, because different readers make that complaint for different reasons. Some readers think parentheticals are terrible; I love them. Some readers hate third person narratives; they're my preference. Many readers don't notice homophone errors; they drive me crazy. Some readers love long, complicated sentences which sound lovely but have no meaning; I think such sentences are a scam, and they make me angry. Without the details, none of us have any way of knowing if that "horrible writing" is really what we would consider horrible.
Similarly, my bar for character stupidity may be set higher or lower than someone else's. I may be more or less inclined to notice continuity problems. I may have different areas of knowledge and expertise, making me more or less tolerant of research fails.
In short, the details are there to make my review as helpful as possible to other readers.
And yes, if your book isn't selling and you don't know why, maybe negative reviews will clue you in to what you did wrong. But that's not their purpose, that's a side-effect. Bluntly put: if you are looking to readers--your paying customers--to tell you how to improve, then you've waited too late to learn. That's the sort of feedback you should get before you publish; when you demand it afterwards it just adds insult to injury:
You mean you not only charged me to read this terrible excuse for a "novel", which should never have been published at all, much less for pay, but you think you deserve free advice on what you should have done differently?
You deserve nothing except to be forgotten and never read again.
Authors have plenty of resources to help them polish their work, and a number of ways to learn their craft. Take some writing courses. Attend writing workshops. Join some writing communities online, and write not for pay, but for practice. Let other people read and critique your efforts, and listen to what they say with an open mind. Read. Then, after you've learned about the differences between one type of narration and another, and what it means to "show not tell", and how to write and punctuate dialogue, go write your novel. Submit it to an editor and a proofer and a beta. Polish it. Do the work it takes to be a successful author.
Then publish your novel, and ignore the reviews. They're not for you, and it's too late to be seeking any more advice.