I was on MangaStream the other day, seeing if Hoshino or Kishimoto had updated their manga, when I stumble upon a title by the name of Hajime no Ippo. It was on chapter 940, which made me think: "Oh hell naw, what could they POSSIBLY be doing to make it drag out THAT LONG?" Really, if you're a fan, I wanna know. No, nevermind, I'll just Google it when I care enough.
I can't speak for anyone else, but if an anime/manga is too long or too far ahead, I usually don't even start it or give up finishing it. (Expect Sailor Moon, I'm not giving up on Miss Moon.) I've been meaning to watch Katekyo Hitman Reborn or Bleach, but it seems so far ahead I throw in the towel. Maybe I'm just lazy. Probably. I told you in my intro I'm lame. The longest ones I've been watching are Naruto and DGM, and that's just because I've been reading/watching them since day one.