Getting reviews can make or break a book. When writers try to manipulate the process, they often run into problems. New or frustrated authors try to buy reviews, and a cottage industry exists that feeds their desires. It almost always leads to a failure that can destroy the writer’s reputation and any hope of ever “making it” in the industry.
Amazon, the recognized leader in publishing in cyberspace, does not like people that promise good reviews for money. If your reviews come from an established pay-as-you-go “Review Mill,” your reviews might vanish. The Review Mill itself will probably face litigation from Amazon.
Amazon’s ratings algorithm can punish any author who succumbs to a bought-and-paid-for shortcut. One writer, years ago, published a book about gaming Amazon’s system. He became a best-seller. He was a pretty good writer. The industry punished him. It’s hard to find his work anywhere nowadays.
That’s not to say that reviews cannot be bought. Kirkus makes a handsome profit doing it. But they do not associate the price paid with the judgment given. If you write a bad book, they will tell you it’s a bad book. You earn the extra insult of paying for the news.
Another problem for a lot of writers is “buddy reviews.” They are easy to spot, data-wise. If a reader rates a book without ever having written a review of another book, that’s often the sign of a “friends and family” buddy review. Anonymous reviews, shown as coming from An Amazon Reader, are a dead giveaway. Amazon will not remove the review (they rarely do this; they want to sell books). They will, however, probably downgrade the value of the review. Just as they probably downgrade the value of reviews that do not get “useful” ratings.
On the other hand, if your mother has reviewed dozens of books and gives yours a 5-star review, I believe that Amazon will respect her opinion and rate it accordingly in their data geometry.
If professional, established writers decide to swap reviews, and they have both reviewed other books, I believe that Amazon will respect their opinions.
That’s my thumbnail sketch of the world of reviews. I must emphasize that the algorithms with which Amazon judges a book’s popularity remain (and should remain) a closely-guarded secret. Place as many grains of salt on my opinions as you wish.
If you want to get a 2nd, 3rd, 4th, 5th, 6th and 7th opinion on the world of reviews, study the “review” threads on this list from the Midwest Book Reviews organization. Most of them contain important lessons to learn. Some of it might depress new writers.