I have seen so many negative comments on others' works and it's really upsetting to see. If you notice mistakes in someone's spelling, grammar, or maybe an issue with the flow of a plot then I can assure you, any author is very happy to have your input. However, there is never a need to say something like "this is trash" or "you suck". If you really dislike a work that much, then just walk away. Instead of wasting time commenting shitty things on people's stories, why not use those precious moments to click out of the work and go find a different story that you actually enjoy