rating?

This is a general question but it fits in with this flick as well as any. Just how do people vote here on IMDb anyway? I get that not every film is a 10-star treat or a 1-star dud. That's a good thing. Getting a range of votes is more helpful than everyone just saying perfect or terrible. But how can someone give 6-stars to a film which they claim is "One of the biggest disappointments of 2003", "a Hollywood bust", "surprising bad", "wasn't done very well", and "Only see this if you wanted to see how they failed to make a good movie." "what really kills the movie" etc. What on earth would earn a 1-star rating from this person, a film which you literally could not watch without loosing your meal and then dropping dead?