Stan Lee said somewhere that he'd only ever written stories that he, himself, was interested in reading, and that he didn't think a writer could do their best work if they were writing for somebody else, i.e.: an audience, because you can never know what any one else really thinks or wants.
It's obvious that Stan's approach to writing has more than proven itself in the marketplace, but I'm not convinced his idea of audience is the same as mine. Like myself, Stan abhors the thought of deferring to an audience especially if one conceives of it as a demographic. Strictly speaking, however, audience, need not be exclusively conceived in this manner. Indeed, it is much more useful to work with the idea of audience as a character, someone to whom the story is addressed, that the storyteller wants to change in some way through the experience of the story and its characters.
Like many others, Stan bi-furcates the nature of the storytelling experience into us and them - those 'characters' that exist 'inside' the story, and those 'real people' that exist outside of it, whereas my view is that its characters all the way up and all the way down.
If, as Stan claims, "you can never know what any one else really thinks or wants" how is he able to effectively dramatize the emotional states, needs and fears of the characters that populate his story worlds? He would probably respond by saying that he had created the characters, but that the audience was already there, waiting and watching. And he is right if you stick to the idea - or prejudice - that an audience is nothing more than a measurable demographic, a faceless mass of economic, educational, societal, legal and spiritual circumstances.
What writers, especially new writers, need to understand is that character-based storytelling is not merely a way of describing the way a character's motives and actions inform a narrative, but a visionary attitude that allows the writer to grasp the fact that not all of the characters necessary for 'finding' (writing) the story exist inside the screenplay. Audience, itself, like the dramatis personae of the script, is an act of the imagination, and it provides a valuable, contrasting perspective to the one that the writer qua writer usually employs when looking at his/her work. The notion of audience-as-character allows the writer to shift his/her psychical distance to the story by momentarily becoming the audience/character, and thus altering the perceptual possibilities. The writer begins to look not only at the relationships that exist among the characters in the script, but also at those relationships that exist between and among the writer, the writer's audience and the tribe or tribes to which the writer belongs and whose influence informs and impacts upon the decisions that both the writer and the characters in the script are making in concert with an audience character and the tribal circumstances that provide the underlying values, proclivities and contexts, in which all the characters are acting.