Why are ghosts supposedly scary?

Answer 1

In my opinion,most ghosts aren't scary. They're just human, but dead. However, they can still be scary. First of all, some ghosts were horrible, cruel people in life and stayed that way after their death. Those are the ghosts who are more likely to hurt people. What makes that worse is that most people cannot see them nor can they kill them. Also the ghosts that aren't even human, aka daemonic, are definitely worth being scared of, but they are least likely to encounter. Unless things are really creepy, don't worry about ghosts. Like I said, they're mostly human.

Answer 2

because they do not understand that ghosts are harmless spirit traces and think there there to hurt people