My personal feeling is that poetry should come from the heart. This being said, the best poems are those that run in some form a stream of consciousness. There can be sentences of sorts, even if they cross line breaks, but the thoughts simply flow from the poet. If authors start to tinker too much with their poems and make them “just right” in their own mind, the spontaneity of the poem begins to be lost.
Now, does this mean that you shouldn't edit your poems at all? Absolutely not!
I urge you to read through your poems just like any other piece of writing. Print out a copy so that you can see it printed on a page and above all, read it out loud. Poetry and song have long been intertwined, so hearing how the words sound against one another can be a powerful tool for a poet trying to figure out if a poem it “done.” (If you have ever read Dr. Suess out loud you know exactly what I mean)
One last note about poetry that I’m sure everyone has heard but not every quite agrees with. It doesn't have to rhyme to be poetry. Just because Shakespeare, Coleridge, and Poe all did it, doesn't mean you have to. Use your own style and don’t be afraid to experiment.