It seems to be designed to discourage people from reviewing.
First it is very contrary to the principle of least effort. It takes so many steps to get there. After reading, you have to go back to the story's index page. You have to scroll down. Then click Reviews. Then you have to click Write a Review. Then an very cramped dialogue box would open. There is so many steps to get there and the final interface isn't comfortable or attractive.
This is actually is a very well known tactic to discourage users from using certain features. Like, did you try to delete your Facebook or Amazon account? Do you know how hidden the feature is to the point that you actually have to search online? The review feature in SH didn't go that far, but it still goes in that direction and similarly discourages people from using it.
Also, the reviews and review feature is not intuitive. The reviews and the means to reviews is in an illogical place. It is beside
Table of Contents. Like, what is the two doing together? Anyone browsing casually will fail to notice it and when they go to the index page to look for it, it being beside table of contents would make many overlook it. And even if you click the review tab, the
Write a Review button is so indistinct. It blends with the rest. You would not remember seeing it. It is made to be very inconspicuous. You have to take the effort and look allover for it.
Again, this is another tactic used to discourage people from using certain features (or things they just don't want you to notice).
It is one of the worst because SH seems to not want you to leave a review at all.