Perhaps I don't give "slasher" films a chance, but someone wandering about with a machete (or whatever) terrorizing people just doesn't interest me. For the same reason, I don't much care for movies where some "monster" is just running around after people (e.g., a giant spider or thousands of small ones). There has to be something behind this that explains why.

For example, Interview with the Vampire takes you back to where/how things start/ed which increased my interest in the film. There have been some efforts to backtrack the Dracula theme to how he started that were interesting.