I will not leave reviews for books. I will review shoes, paints, clothing, rugs, service providers, dog foods, shampoos, kitchen gadgets, etc. I will not review books. I will not publicly comment on the works of other artists in my field. Regardless of genre. I have made one exception. I will not make another. This makes my Goodreads page very dull, 'cause it's all about me, me, me. SorryNotSorry.
In my experience, there are three general categories of authors who do review books:
The Hat-Tip: There are plenty of authors who actively review the good, the bad, the ugly. There are authors who will only review a book they feel deserves five stars and heaps of praise. There are authors who will only review books 30+ years old or books far outside their genre. These authors ask for nothing in return for the review; they do it for the love of reading and being active in the readers' communities.
The Tainted: There are authors who will review in exchange for a review. This is a great temptation, especially when trying to trigger the magical algorithms to increase the visibility of a book. This is very common in the authorverse; so much so, that it's an unspoken expectation among certain circles. I withdrew from those circles...then reached for the bleach and a wire brush.
The Terrible: There are authors who use reviews as a portal to refer potential readers over to their books. There are authors who eviscerate anyone they perceive to be competition. There are authors who engage in reviewer wars--for books they have written and for books written by others.
I will not leave reviews for books. It's a respect thing in which I endeavor to treat my peers equally; regardless of their ability to entertain with a story. At the end of the year, when we Word-Whores list our Top Reads, that's closest I'll get to a review. Even then I have to be careful, because...opinions, I have them. Often in caustic abundance. For all that it is easy to elevate with praise, it is equally easy to condemn by omission.
I'll stick to writing the books. I leave the reviews to the readers, gods bless 'em.