It saves time. Instead of spending a long time thinking about how to develop a full story from a single sentence, the AI can do it quickly. So if you're short on time but still want to explore story ideas, this is a great option. Let's say you write 'The bird flew over the city.' The AI can generate a story about the bird seeing different parts of the city and having an adventure, and you get a story concept in no time.
Another advantage is that it can improve your writing skills. By seeing how the AI expands on your sentence, you can learn different ways of adding details, creating characters, and building a plot. For instance, if you write 'The young woman entered the café.' and the AI makes a story about the woman meeting an old friend in the café and having an interesting conversation, you can study how the AI introduced the friend, described the café, and developed the conversation, and apply these techniques to your own writing.
One benefit is that it can spark creativity. When you see the story the AI creates from your simple sentence, it might inspire you to think of new ideas. For example, if you write 'The old man walked into the library.' and the AI creates a story about the old man finding a magical book in the library, it could make you consider different plotlines for your own writing.