Poems are expressions of an unconscious, framed in words.
The unconscious does not have access to language. That is a conscious meaning-making and expressing step. Language requires sequencing which the unconscious does not do.
This makes poems an in-between, a means of plucking the metaphoric into words.
The unconscious only communicates in metaphors.
And this makes poems, a highly effective way for one unconscious to communicate with another.