Let's say music is needed for only 43 seconds of film. You have to score it so it is an entity, so it won't bother anyone when it ends so quickly. Or if a song runs 2 minutes and 45 seconds, but the titles run a minute longer, you have to arrange that song so it doesn't get repetitious.
“I tremble for my country when I hear of confidence expressed in me. I know too well my weakness, that our only hope is in God.”
“Well, it's an adventure story, and a Bildungsroman, of course, but there was also the intention to describe a culture that had been seen in rather narrow terms.”