Yes, that's the problem... you've just described the entirety of the story in 2 sentences. That's no more than a premise for a movie, but in this case it's stretched so thinly that it makes up the entire story.
It's not that I don't like "slow" movies, eg. one I know is appreciated around here is Spirit of the Beehive, which is wonderful. I'm glad others enjoyed this, but for me there just wasn't enough meat on the bones to provide entertainment.
<edit> I think my problem is that I just didn't find it that creepy or effective... you could say that Suspiria has a simple story too, but the atmosphere and set pieces are so effective that they're strong enough to carry the complete movie to the highest level. In BSS I was just bored and waiting for something (anything!) to happen, but I guess if the atmosphere alone worked for you then it would be enough by itself to make the movie a success.
Last edited by sinister; 01-30-2013 at 10:54 AM.