Recently I started reading Supernatural fanfiction and I have to say that I am amazed by the amount of absolute awesome fics out there. Nevertheless there is also a lot of annoyance to be found in fanfiction and here are my Top5 Fanfiction Turn-Offs:
1) Dean smoking // I don't know why so many authors think it would fit for Dean to smoke or that it makes his character cooler or whatever .. me, I close a story as soon as that comes up, no matter how good the story is. It's not because I am a convinced non-smoker myself but rather that I see absolutely no necessity for adding character habits that actually don't exist and it messes with my ability to identify the character I read about with the one I know from the show, it's a simple atmosphere and authenticity killer
2) Swearing // The amount of swearing the boys do in some of the stories is really off putting. In the show their language is actually pretty well mannered and not very slang-y (well at least from a non-native speaker's PoV). We hear them use Bitch, Son of a Bitch, Dammit, Hell, Frikkin in the show, but what most authors seem to favour (and I mean like constantly) is 'Fucking' .. which I actually don't even recall the boys ever using, or if they do it's so rare it never stuck with me.
3) Food // I am not sure where exactly this comes from, but Dean is pictured as the 'greasy hamburgers and fries' guy while Sam is Mister Health Food. Throughout the show we see them in various different locations, which all look as if they serve homemade food. Simplifying and generalising from none to very small evidence in the show is a very annoying treat for me in fanfiction.
4) Banter // The constant re-iteration of one-liners that are actually said in the show to give a story more authentic SN-feeling. The point of snarky one-liners is that they spring from the moment that inspires them and they are not usable like idioms or similar phrases. So either the author is skilled enough to catch the banter between the boys with genuine originality or he/she better leaves it.
5) Touchy-Feely // Dean’s infamous „No chick flick moments” from the pilot is stretched thin in fanfiction to a point where it becomes completely ridiculous and non-believable, since over the course of the first season Dean is shown as a vulnerable and very emotional character, who is absolutely able to open up if the situation calls for it, especially towards Sam, but also to the random victim in distress. A lot of stories choose to ignore everything we get to know about the character from the Pilot on .. which completely annoys me.