The stories are scary because of the imagination brought my the author to the piece of writing. The supernatural character that usually scares the reader. Especially their detailed characterisitics like a girl wearing a white gown with her hair down, or the priest with his head on his hands, the old man that lives alone in an "abandoned house".
Usually the story is told in a first person point of view. When the introduction starts, the narrators usually talks in a horrifying way. Throughout the story, hyperbole words are used to infacize suspencful moments. For example "crreeaaaakkk says the door while I slowly tiptoed inside the room."
The situations in scary stories are usually suspenceful. They make the reader so stressed out of what's coming or what's inside. Including scary sound effects on movies or records. Adding sound effects really affects the readers emotion. It makes the reader get into the story making them read even faster and gets them even more scared.
What really scares the reader is the surprise and suspence of the story. We don't really get scared while reading it we just get a little thrilled. What makes stories scary is when we, as reader's think that it can happen to us. We start thingking of what pops up or what's in the dark. So technically the stories gives us idea of something that's out there and is going to get us.