Forget the elevator pitch. You only get four words.
If you want to start a business or launch a new project, you need to be able to describe your effort in four words.
If you write a longer story, the door cracks open to ambiguity; you can start to hedge your bets, get vague or abstract. Stick with four. It means you must identify a subject, an object, a verb and maybe one descriptor or refining notion.