He’s been told to destroy everything in the city they’ve conquered, but how can that be possible when they come across something beautiful or valuable?
A little is left behind, then: enough so it doesn’t feel so wasteful, and to feel like they’ve won, which they have. It helps more, because it’s easier to believe something they can see.
However, not everyone would appreciate the sound of their victory, and he’s not sure whether it’s because he’s missing something or whether they’ve been misunderstood. But he’ll never know for sure, because the rising sound of triumph is drowning out all other voices until he can’t even hear himself think.