Art Criticism of the Viewer?

"It is not the object expressed, but the depth of the subject expressing it, that most defines art." (KW)

Agree or disagree with that statement, nevertheless do we not judge art by the artist? Miles Davis, Pablo Picasso, Bach, Alex Gray, your favorite writer, your favorite musician, possibly we will state that art is defined "in the eye of beholder", but then I ask, why do we care to know so much about the artist's life, thoughts & deeds? Recently I had a dialogue with a friend about an artist on a television show; the artist was portrayed as a drug-addicted, self-centered, womanizing character. The question he asked was; why can an artist not be normal for them to be interesting / talented?

My answer: The artists can express different worldviews within an integral perspective, and we as the viewer are addicted to their experience. The final product can sometimes be a let down but the process of the compositional development and the environment that it was conceived in is forever tantalizing.

"And that is why ultimately, profoundly, inescapably, it is the depth of the subject that provides the objects of art."(KW)