A song is a beautiful creation that is an intangible (an object that does not have a physical presence that you are unable to touch or grasp). A song is built of several interconnecting parts and can achieve a myriad of effects. Yet, you cannot hold on to it.
But you can feel a song deep inside of your being in a visceral way. A song can evoke inspirations of hope, anger and rage, extreme love or hate, laughter, sadness, joy, exhilaration or any nuance of an emotion. A song can be very powerful, but you cannot hold on to it. It is also difficult to put a value on something that is intangible.
The art of writing is rewriting.