Opinions, everyone has them, etc. It's cool to express them too, but try to be constructive with your criticism. This is an archive for stories, some of which may not be the shining pinnacle of awesome or grammar.
Telling people their stories suck without offering any sense of why or how to improve is nothing short of trolling or drama. It's not cool to say a story is shit (unless, y'know, it's supposed to be) and not offer any ideas of how the author can improve.
Sure, you may be thinking, but Uncle Cleric! Someone said your story was shitty. Surely you are the butthurts.
Your thoughts would be of the wrongness. I am an English Major. I know how to make the writings. I also know and accept that not every single work I squeeze out will be solid gold. The same should be true of all writers. I write the bad ones to learn how to better write the good ones. Practice, in other words.
But, as a writer, one expects that if there is criticism, then there should be a suggestion as to how the writer can better his stories. Think back to High School (I hope you have to think back, or at the very least completed it) when you were made to give feedback in English class. Saying DURR IT'S GOOD should not have been a valid response for feedback (and may those teachers that let it count for appropriate feedback burn in English Teacher Hell).
For aspiring writers, nothing is more damaging to one's self-confidence than hearing what they have written sucks. Now, if you tell them it sucks, and here's why, it would be taken infinitely better because they can learn how to better themselves.
Also, I know that when I write (and if you do too, you should know) I will not be able to please everyone who reads it. Not everything is written for every audience. It's OK if you don't like something because it's not your cup of tea. That doesn't mean that because you don't like zombie stories that the story itself is a steaming pile of crap.
This is a big wiki. If you don't like a story, DON'T READ IT. Simple as that. No one will take any heed to you saying something is shitty if that's all you have to say about a story. Zero fucks will be given.
TL;DR: Don't comment on pastas just to say they suck. If they suck, everyone should know it. If you don't like a story, you don't need to show your displeasure. It makes you look like a damn fool.
Also, I think (Xan, Ben, let me know how you feel about this) that posting "Shitty." or "WORST PASTA EVAR MARK FOR DELETION CUZ IT SUXXORS" should be considered wikidrama and subject to DA RULES as such.