Whenever a human writes/improvises a fictional character, it is typically to communicate some concept or goal to other people. The fictional character--even a simplified author-insert speaking "directly"--is part of how the medium works.
So in a way your question is equivalent to: "Why do humans have intents and minds but LLMs don't?"
So in a way your question is equivalent to: "Why do humans have intents and minds but LLMs don't?"