As a graduate composition student, I've had the great fortune of being able to study with and pick the brains of a number of esteemed composers. Though I've never done so myself, I've often thought about teaching composition, which inevitably brings questions of aesthetics--what sort of criteria to use when evaluating a work, to what extent do I allow my own biases and opinions to shine through, and how to communicate my feedback in the most effective way. If we take the first two questions alone, it is easy to apply them to another aspect of being a musician: going to concerts and considering the artistic value of a piece or a performance. But often we don't get the opportunity (or we dismiss the option) of giving feedback to the performers and/or composers involved. It's my belief that if more concertgoers are able and willing to give constructive, helpful feedback, and if musicians are able and willing to receive feedback (and be able to filter through that which is NOT constructive), the overall artistic value will increase.
Feedback is a difficult thing, though--often it tells more about the receiver than the giver, for many reasons. In the context of concertizing, the audience/listener only perceives certain aspects of the music and the performance, and cannot give feedback on aspects that were outside his/her perception. And, the listener organizes these perceptions in a way that is meaningful to them, selecting certain aspects out of thousands that may be commented upon, according to the reaction they had to the music. And even if they are aware of these particulars, the listener's internal feelings and rules for commenting determine the style, choice of words, emotional tone, and non-verbal cues that comprise the entirety of the feedback. So, since it's clear that feedback tells more about the giver than the receiver, why bother to seek it out at all?
It is human nature to want to get information. Especially in an often nonverbal medium such as music, we want to be able to communicate our ideas with one another in a meaningful way, and often that involves the use of feedback. Artistic value is intrinsically tied to audience perception, so it is imperative that we understand what the perception is, and how to respond to it. So, learning how to ask for, receive, and appraise feedback, in my mind, is a worthwhile goal as a musician, and one that is absolutely necessary as a human being.