I love horror films. I'm sure most of the people finding me recently do as well, based on the links that are being followed into this blog. Why are so many horror films so very very bad? Like any genre, there are certain rules and constraints that everyone follows. I'd love to see someone be successful with something that doesn't conform, but that makes it an even harder proposition to write and produce.
You all know some of the rules. Bad behavior is punished. The hero is blameless. Children should be in mortal danger, but they can not be eviscerated. If there is a woman who has been wronged, she has to get her revenge. There are others. You have to have a handful of false scares. The hand that grabs the shoulder from behind turns out to be the boyfriend not the monster. Around half way through the movie, the audience has to understand why the scary events are happening, like they moved the headstones but not the bodies or we are polluting our environment.
But for me, most importantly, if you have otherworldly or preternatural apparitions, ghosts, monsters, etc., their powers have to make sense. I need to understand exactly what their powers are. If each person who gets killed, dies in a totally different way from all these different powers the nasty-thingey is capable of, I'm going to get very annoyed. If your nasty-thingey is a ghost who can not travel through a quick Scotch-taping of the crack under a door, then how come this same nasty-thingey can lift a human body and send it flying through a window? If there's Scotch Tape keeping a door closed, how about you send a knife flying through the air to cut it? You can't change the rules for every scary scene you want to put in your movie.