I think that there are two factors that make a scary movie scary. One, the music, and Two, the suspense. When you think about it, if a creepy monster with one eye and a bloody head( sorry for the details but I want to make my point clear) popped up on screen and the spongebob squarepants theme song was playing in the background would you be scared? Probably not! I know for a fact that I would start cracking up if that did happen. Hope I helped! :)