openAI models are good at solid, fluent academic style prose. DeepSeek R1 can sound fresh and can use more "voices" that feel authentic to the reader. Grok-3 is close behind.

Writing good prose is a far different skill than coming up with a compelling and innovative plot and style.

As a data point, OpenAI now blocks o3 from doing the "continue where the story left off" test on works of fiction. It says "Sorry, I can't do that".