Silent Hill: Classics are scary, but why?

Travoga in classic Silent Hill

Games don't lead you by the hand, it's not always clear where to go, and even though I wasn't particularly slow, it's still uncomfortable to wander around locations without being sure whether I missed something important, whether something scary is waiting around the corner. And there are all sorts of devils running after you.

It suits the genre, yes, but specifically in classic silent films I really feel anxious.