What about in cases where there is no one "solution" due to an environment that you are embedded in or something: like writing a good song or making a painting or writing a nice poem for a friend?
Art is a bit like white noise or a fluffy cloud: You can see everything you want in it – and that's exactly what you see. So basically everything qualifies as a solution. This is easy to see with poems or more abstract music (like drones). But I think the same holds true for pop music only that there are some rules on top of it and a marketing department that "assists" the consumer a bit in what they should see in it.
