Why don't Readers review books?
There is no one answer, but I believe the average reader may think their opinion doesn't matter. OH BUT IT DOES! Especially to new authors such as myself. Stephen King doesn't need 5,000 reviews, but I would enjoy having 50. First, reviews help the author to know how the book was received, and as a tool to improve their writing based on those things a reader may not have liked. Second, the author's exposure and ranking is tied to the number of reviews they receive. Third, it's not that hard to do. A simple star rating and a statement whether you liked the book or not will suffice. No need to feel you have to write a review as wordy as some. But if you want to, here is a link to Writing-World.Com that provides a guideline: www.writing-world.com/freelance/asenjo.shtml
I very much appreciate those that take the effort to write my reviews.