A poem can say in four lines what an argument needs four pages to approach, because it isn't trying to convince you — it's trying to show you something you already half-knew.
Compression is not simplicity
Cutting a feeling down to its essential words is harder than explaining it at length. What remains has to do more work with less room to hide.
Saying it in public
Publishing a poem means admitting, on purpose, that something private mattered enough to write down and hand to a stranger. That's the quiet courage most poems ask of their writers.