We all have experienced them at some point in a game or a show, at if you're like me it has irked you to no end.
So which one annoys you the most?
For me it's either logic flaws (Damn you Mass Effect and Battlestar Galactica) or Deus Ex machine
Fuck you Deus ex
I have no specific problems with any of these unless they break suspension of disbelief, but that can be caused by pretty much any of these things.
Although if it comes to things I hate about games and shows it's lack of story and overkill of special effects. And that, unfortunately, seems the major selling point of most modern stuff.
It can be annoying when you're trying to immerse yourself in a fantasy story and elements such as the ones mentioned above can ruin that.
Pretty much what Plu said.