They leave a lot to the imagination. Consider 'The empty swing moved by itself.' It doesn't explain why, and that's what makes it so terrifying. Your mind fills in the blanks with all kinds of horrible possibilities, and that's the power of very very short horror stories.
Many horror very short stories rely on a sense of isolation. The characters in these stories are often alone or cut off from help. In 'The Landlady', the young man is alone in the boarding house with the strange landlady. And they usually have a strong atmosphere. Whether it's the oppressive feeling in 'The Yellow Wallpaper' or the general sense of dread in 'The Monkey's Paw'.
They are concise. For example, they can quickly set a simple scene like 'A fish in a pond wanted to see the ocean.' without much detail.
The characteristics of a very very very short story include simplicity. It doesn't have complex plotlines or numerous characters. For example, 'Bird flew. Sky was blue.' Also, it can be highly suggestive. Since it's so short, it makes the reader think more. Like 'Light went out. Silence.' It makes you wonder why the light went out and what the silence means. These stories are often about capturing a moment or a basic human experience in the most minimal way.
One characteristic is their ability to convey a big idea quickly. For example, they might introduce a unique concept like a new form of time travel or an alien society in just a few paragraphs. Another is their often - intense focus. Since they're short, they usually center around one main idea or event, like a single encounter with an alien in a very short story.
A very very short story is marked by its extreme brevity. It usually doesn't have elaborate settings or complex subplots. Instead, it aims to convey a core idea or feeling quickly and effectively.
The last person on earth sat alone in a room. Then there was a knock at the door.
They are often concise. For example, they can be about a single, brief, and strange encounter like seeing a strange small object that gives off an eerie feeling.
Very short short stories are often concise. They usually focus on one main idea or event. For example, they might tell a brief encounter between two people that reveals something about human nature in just a few sentences.
Very short scary stories often rely on common fears such as the dark, the unknown, and being alone. They use vivid but minimal descriptions to create a sense of unease. For instance, a story could say 'He walked into the empty house. The creaking floorboards were the only sound. Then he saw a shadow move.' This builds tension without a lot of extra words. Also, they can play on superstitions like ghosts or curses to make the reader feel scared.
One characteristic is their brevity. They convey a complete idea or story in just a few pages or even paragraphs. For example, they often have a single, focused theme, like love in 'The Gift of the Magi'.