Consider the poem's purpose....

*considers

Is this a question about a specific poem? Or are you asking the general purpose of a poem?

In general I'd say it is to convey thoughts through more artistic means. Poems work on a more emotional level.

Wilfred owen's war poems for example were constructed by him to convey the horrors he saw on the battle field. Sometimes a poem is just a fancy i.e. It serves no real purpose except to give you a moments experience. Some poems ask questions. Some give praise. Asking a poem's purpose is like asking the purose of a thought, there is a different answer each time.

Do you have a specific poem you would like to go over?

A question, and I question the question.
Questioning myself to produce answers,
which I question and then strengthen.
All the time questioning if I have understood the question.

So I think to be safe I'll end my text with a....
question?

Nah a poem.