I imagine a song is written in many different ways.
A composer may write a little jingle, and a lyricist puts words to it - and they go on from there.
Or, a lyricist may write all the words, and then a composer puts music to it.
Or, a composer writes the music, and then a lyricist puts words to it.
I'm sure the effectiveness depends on each composer and lyricist individually, but my question is this:
I am currently writing a musical - my first attempt at a non-play. Not being a composer - do I write the lyrics, or wait until I meet with a composer and work with him/her on it together?
"The Spectacle has, indeed, an emotional attraction of its own, but, of all the parts, it is the least artistic, and connected least with the art of poetry. For the power of Tragedy, we may be sure, is felt even apart from representation and actors. Besides, the production of spectacular effects depends more on the art of the stage machinist than on that of the poet."
--Aristotle