The following was extracted from Judith Briles' guest post entitled 'As the Author World Turns on Amazon Book Review Policies' on Joel Friedlander's The Book Designer. The Blog was posted 21 March 2019.
Authors need reviews on their books. Lots of them.
Once, there are 25, the [Amazon's] robots warm up. More than 50, expect to see cross promotion: book covers pop up on “like” books … “Customers who bought this item also bought …” meaning that your book cover gets displayed on other author pages.
As your reviews build up (think more than 75), Amazon does email blast, suggesting your book cover with the live link to viewers of the site that have shown an “interest” in your category with their searches. How cool is that?
So yes, reviews do count. Big time.
While Judith has anecdotal evidence supporting her claims about the effect of Amazon reviews the comments under the post make clear that this is a contentious area, and even if Judith is correct, as she wrote in response to one comment: "Guaranteed – Amazon always changes its system. What is good today, may not be next week."
Anecdotally, however, I just got an email blast from Amazon.com suggesting I might like Melissa F. Olson's new book Boundary Broken which had, when I checked 69 reviews. OK, OK, Amazon knows that I've bought the previous three books in the series, but still ....
Anyway, regardless of how important reviews are, I think any author would agree that any positive review is helpful, and the more the better.