When things become so hyped, peeps get turned off by it. Or they expect it to be amazing (eg. the korean drama Coffee Prince), only to discover it to be just better than average. And you realise that if they hadn't heard the hype they might have enjoyed it a lot more.
In some cases, fandom does make everything better. I'm sure I'd have lost interest in HP after so much public mania, (like my sister who has yet to read books 6 and 7) if not for the sporking, crack and awesome fanworks that showed that even juvenile epilogues can be a source of entertainment and in some cases, oddly interesting fic :)
Hype means that everyone and anyone is talking about the thing and we have comparisons where "The Twilight series is the next Harry Potter series" and then all the Twilight fan
Fandom means the fangirling/fanboying occurs in less public groups where one can go crazy over the subject matter, make badges and cookies and scarves all about your OTP - while not trying to convince random people that yes Zuko and Katara are MEANT for each other and who is this Aang person anyway? Nevermind that all those people care about is someone called Toph...wait, oh yeah, that short girl. Pfft, she came in during Season 2 and is obviously not a main character. Zuko/Katara FTW
Long story short, these two posts and more specifically this thread made me wonder if there was a place on LJ where peeps can share their dismay over Twilight mania. A place of refuge from the sparkles of vampire glitter that leave you cringing. Please tell me there is a community, please.