Anatomy of a chorus
A chorus should outlive the song. How many ideas it needs, what repetition is for, and why “simpler” is almost always harder to write.

A good chorus rarely looks impressive on paper. It might have eight words, half of them repeated, with a rhyme you can practically see coming. Then it lives in your head for a week.
One thought, please
A verse can change direction. A chorus benefits from being a little dumber. It picks one reaction and sticks with it to the end.
A chorus needs a shape
Not necessarily four neat lines. But listeners should know where they’ve landed. A repeated word, a return to the first phrase, the same melodic gesture: they all create an outline.
One phrase repeats with a small change.
The beginning returns at the end.
Each line turns up the pressure a little.
The phrase ends sooner than you expect.
The words need to stand up to repetition
A complex metaphor can impress you once. By the fourth repeat, it’s demanding your attention. That’s why short verbs, pronouns, and concrete words suit a chorus.
You can admire a verse. A chorus makes you want to scream.
Five checks
Can you remember the main phrase ten minutes later?
Does the chorus have a single melodic shape?
Does the emotion make sense without the second verse?
Is the main line starting to get on your nerves?
Is there a part the crowd will pick up on its own?
The idea in a chorus is usually simpler than the one in a verse. That’s no concession on quality. It’s the hardest-earned simplicity in the song.