Some art is complete when the artist finishes. Some art is simply a roadmap.
I don’t think people always reflect on the difference as they experience art.
John Green likes to say that when he publishes a book, it doesn’t belong to him anymore, it belongs to his readers. The interpretation you bring as an individual reader is integral and part of the artistic experience. While he shapes it with his words, he doesn’t get to determine your experience as a reader. Even so, the art work is essentially complete when it goes to print.
It’s the same for a Van Gogh painting: when he put his brush down, the artwork was finished.
But a composition is a completely different artistic creation. (At least in the Western Art Music tradition – it’s different for a singer-songwriter.) When I compose a piece of music and deliver the score to a commissioning party, I haven’t delivered the artwork. The score doesn’t make any sound. There is no artwork without its interpretation by an ensemble.
In fact, it’s not an artwork at all. It’s simply a roadmap for an ensemble to get to the art. Just as I can’t drive on an atlas, I can’t consider a score an artwork.
That’s why I care so much about clarity of notation – because the clearer the map, the closer the artwork will be to my vision.
A big part of the beauty of roadmap artwork is that different interpreters can share different things with the audience – just as different painters would show us different interpretations of the same landscape. Roadmap artwork is collaborative across time and space in a way that other art isn’t.