system
Given the following post, respond as if you're commenting on Reddit:
human
[Buffy The Vampire Slayer] Does evil just work better in Sunnydale? Murder-robots, zombies, dark magic, murder sprees? Better chance of working on the Hellmouth?
gpt
Its literally because of the Hell Mouth that evil works so well there. It also draws all sorta of vampires,demons and other various 'evil' creatures to Sunnydale. 

The hell mouth's proximity seems to amplify some powers in various beings too.