Consider this scenario: You're a new poet. You've discovered poetry and you want to be able to create it for yourself, because it's beautiful; a natural way of expressing yourself. You sit down, your thoughts seem to flow and flow...
You've shown your masterpiece to your peers, and they critique it carefully and thoroughly and though they don't agree on everything and each one points out different things, you find one common complaint: "Your poem has no punctuation."
But, you wonder rather resentfully, why should they consider it bad for my poem to be without punctuation? Others have done it, haven't they? .... haven't they? And anyway, there are very few concrete rules about writing poetry, and punctuation isn't one of them.
1) Lack of punctuation makes the poem difficult to read and understand. As a brand new poet, your lines are most likely normal sentences, like you would find in prose; just arranged differently, and hopefully worded more carefully. If I am writing an ambiguous sentence in prose you would expect it to have a period if it didn't it's possible you could be left wondering where one sentence starts and another stops that is frustrating to the reader rather like this run-on sentence.
2) Think about how many poems you have actually read without any punctuation, or with inconsistent punctuation, scattered here and there like seeds that have been tossed in the air, with no care to where they land. If your answer is one, or none, or three or six, you should increase your poetry intake! It takes a reader of poetry to make a writer of poetry. Even as you read more however, you will probably still find the punctuation-less poems to be few and far between.
3) Again, this is to the new writer! Poetry is difficult; let me tell you that here and now. Maybe it's easy to spew the ideas out the first time, maybe not; either way the work doesn't end there. At least it shouldn't. That's getting into a different subject, but the point is, there are certain techniques that you will not immediately be able to pull off successfully. Rhyming is one example. Rhyming is what most commonly comes to mind when most people hear 'poetry'. But it can be extremely difficult to rhyme successfully.
It is also difficult to know when you can leave out punctuation and still make sense. Or make no sense but use that to bring out the emotions you want from the reader, leave the impression you intend to leave, and be interpreted as you want to be intrepreted. The most accomplished poet might still avoid it because it is very tricky; and risky. There's always a chance, always, that the reader will simply give up because they can't tell one thought from the next.
As a new poet--or rather, as a writer in general--the reviewers are looking out for your best interests. (Or maybe you haven't experienced this scenario and as a result of reading this never will.) They're trying to steer you away from something that will, in turn, steer your audience away from you. And the audience is of course one of a writer's most valuable assets. We write for the audience.
Before you try to accomplish ambiguity or double entendre through lack of punctuation, accomplish it with punctuation, and go on from there. Take my advice: punctuate your poetry just as you would your prose, and you'll save your readers a lot of confusion, and save yourself a lot of readers.