Our sense of a composition largely inheres in how we feel about the individual parts; narrative arcs are almost always essential in drama but (unless there are lyrics involved) often less essential in music. All of this is, I suspect, again symptomatic of human memory limitations. We live, to a remarkable degree, in the present; what happened thirty seconds ago is already rapidly fading from our memory (or at least rapidly becomes harder for us to retrieve).
Gary F. Marcus, Guitar Zero
music