Shared toolkit
Lyrics and poems both use rhythm, rhyme, repetition, imagery and voice. A chorus is a refrain; a hook is an insistent image.
What the music carries
A melody can supply emotion that the words never state. On the page, that lyric may read as thin — which is not a failure, just a different medium.
Testing a lyric
Read it aloud with no tune. Does the imagery still surprise? Does the structure still build? That test separates writing that stands alone from writing that leans on the song.