I had always attempted to write songs and compose larger works of music, but my lack of training certainly was apparent. However by the time I was in my late 20s I had sold a few pieces as soundtracks for documentaries, industrial training films, and a few local commercials. I toyed with the idea of pursuing that as a career and began to look around for a college that offered a course in film scoring. One night I found an educational film on TV that featured a college professor explaining how it was done.
He had chosen a short silent film that was in public domain and proceeded to compose music for each scene. His instrument was an electronic keyboard that was typical of the times and so he wrote some very odd electronic music for this old film all the while explaining his choices. Near the end of the program he played the various scenes with his score. Artistically it was interesting but commercially it was awful. The music completely upstaged the images and no director would tolerate that.
The fact that I've had some modest success scoring films, and even have a listing in the IMDb for a small contribution that I made to a film a few years ago, does not make me an expert nor give me license to teach a course. I think it's important to understand your limitations and learn to work within them as you work to expand and stretch them.
In 1984 I listened to a new work performed in concert by guitarist Julian Bream. He had commissioned a piece from Sir Michael Tippett that was influenced by a painting by Picasso. To the untrained ear it sounded as though he had started in the middle of a piece, rambled around for twenty minutes looking for the correct notes and then just stopped. The sparse applause at the end was more in gratitude for its conclusion than for the performance itself. In a later conversation with an artist friend I attempted to give some defense of the piece, "I did occasionally sense the cubism in it", I said. He quick reply was, "Yes. But even Picasso knew where the edge of the canvas was."
While boundaries can be restrictive they can also require the artist to become more, not less, creative. Pop songs are usually 3 minutes or less. If you're a song writer you've got to say what you've come to say and then get out. Television programs have similar time restrictions. My friend Sande Backes Foster writes some marvelous haiku. That is a seriously restrictive form and yet her creativity soars.
Although there are some notable exceptions, I find that an artist that simply ignores boundaries and kicks down the fences usually creates forgettable art. For most, the boundaries help to concentrate the effort and sharpen the focus. So even though Picasso pushed against convention he never forgot where the edge of the canvas was.