I have to say poets use what ever comes to mind!
There is no particular reason for it...
I know when I write my poems, I dont say to myself ok, now I am going to write a poem using a particular form such as internal rhymes for example...What ever I am feeling is what I will write about. What ever order, shape or form that it takes is simply how it will appear on paper.
I think most poets feel the same way. I am simply one of infinity poets.
Hope this helped.
It's mostly for rhythm, like using
Alliteration within a story.
To make the poem sound more natural rather
Than using end rhymes -- which can make it sound contrived,
Chanelglit is right, there isn't much of a reason other than suddenly thinking of something and liking the way it sounds, or its meaning. Sometimes the purpose is solely for the rhythm, which is much more likely.
it's mostly for rhythm, like using alliteration in a story. also to make the poem sound more natural, rather than using end rhymes - which can make it sound contrived at times :)
I agree I have only consciously used this once