I guess target audience might be the wrong term since I'm not really thinking of a target audience in terms of "teenage guys who like sports" and stuff like that, but more along the lines of "people who like slow-paced movies about family drama and adolescence".
For example my favorite film, "A Brighter Summer Day" (1991), is four hours long. It's almost certainly not going to be your cup of tea if you dislike long and slow-paced movies, but that doesn't make it a bad film. It just means that it isn't for you.
I mean - to take the two ends of the spectrum - that some music, movies etc are made because the director/writer wants to make it, because doing so is meaningful to them. They're the ones that get called art, whether good or bad art. Every part is determined by the desires and taste of the creator. They're all about the creators' desires, imagination, experiments, taste, self-expression.
Others are made kind of backwards, first by figuring out the target audience, writing a plot filled with the kinds of things that have made money recently, then making that. Making music/movies by formula. Every part is determined by the supposed desires and taste of the 'target audience'. They're all about marketing and making money.
A work of art comes from the fact that the author is what he is. It has nothing to do with the fact that people want what they want. – Oscar Wilde
Most of our modern portrait painters are doomed to absolute oblivion. They never paint what they see. They paint what the public sees, and the public never sees anything. – Wilde
[An artist] cares about the end-result as a completion of what goes before and not because of its conformity or lack of conformity with a ready-made antecedent scheme... Like the scientific inquirer, he permits the subject-matter of his perception in connection with the problems it presents to determine the issue, instead of insisting upon its agreement with a conclusion decided upon in advance. ...one of the essential traits of the artist is that he is born an experimenter. Without this trait he becomes a poor or a good academician. The artist is compelled to be an experimenter because he has to express an intensely individualized experience through means and materials that belong to the common and public world. This problem cannot be solved once for all. It is met in every new work undertaken. Otherwise an artist repeats himself and becomes esthetically dead. – Dewey, Art as Experience