To be honest, I rarely bother reading reviews much less rely on the star rating. Most reviews are either trolls being trolls or authors/fans rigging said review section. What I usually do is simply go to the Browse section and select a genre I'd love to read (i.e. romance, fanfiction, comics) then select either Updated or Collection.
Updated = I can see that said novel is still active or new
Collection = Number of possible readers = It got to be good if lots of people read it? (I rarely use this method)
Then I read around 5~20 and sometimes up to 40 chapters (depending on available chapters) based on how engaged I got to a novel. Some may consider that 5~20 chapters aren't enough to check whether a novel is truly good or not but this is why being able to write a good Prologue/Intro is a must, it allows the author to hook in readers.
Back when I still used the review function, I honestly tried to write a constructive criticism free of bias as much a possible with a clear format
2stars = I don't plan on reading the novel in the future
3stars = I plan to revisit the novel and see whether the author improved or at least tried to improve on what irked me away from the novel (i.e. grammar, character, plot, etc).
4~5stars = I plan to read the novel up to the end unless there's an unexpected development (i.e. author dropped, somehow it got worse(it's rare but it happens), or simply it went to a diverging path I didn't like).
Sadly, most if not all my reviews of 3stars and below got deleted... Hence, I stopped using it.