First, if you think a poem is horrid, it probably is. With practice you can learn to elucidate why it is horrid. This is a useful skill for poets, poetry readers, and editors or teachers of poetry. Here are some common flaws in poetry:
- Imperfect or erratic rhymes. A good poem, if it rhymes, should either use perfect rhymes throughout or use a clear and appealing pattern of near rhymes. Bad poems try for perfect rhymes and fail.
- Erratic meter. A good poem, if intended to have meter, has a fluent meter that flows gracefully when read aloud. It need not be perfectly regular, as variations on the meter can add interest; but it must be pronounceable. Some forms demand a specific, exact meter and mistakes there count against quality. Bad poems stagger drunkenly from one word to the next.
- Topical trouble. The topic should be clear and interesting. Absent, indistinguishable, garbled, or pointless topics cost the poem points. Especially watch out for cases where two poems are tangled together into one, with competing aspects of the same topic.
- Flawed form. Any poem of a specific form must follow the rules for that form precisely. For poets not skilled in writing to form, there is free verse. Breaking form can be a trivial or catastrophic flaw.
- Mismatched motifs. The form clashes with the topic, the rhythm jangles against the theme, the metaphors are wildly inappropriate, etc.
- Misused techniques. Poorly chosen allusions, mixed metaphors, overused similes, awkward alliteration -- these are examples of valid techniques gone wrong.
- Cliched imagery. Avoid it like the plague! Off with its head!
- ZOMG-EMO-DRAMA!!! Bad poetry exaggerates, whines, mopes, capers, and generally makes an embarrassing spectacle of itself. Good poetry delivers emotion softly, like snowfall -- or slyly, like a stiletto. If you can see it coming, it's probably not done right.
- Pronunciation chuckholes. Good poetry demands to be read aloud; it feels good in the mouth. Reading bad poetry is like trying to spit out a mouthful of rocks, one at a time, without swallowing any. Some sounds create tongue-twisters when combined.
- Cacophanous sound. A good poem sounds delicious in the ear. A bad one makes listeners wince when they hear it. Some sounds don't go well together.
- Prose flavor. This flaw reveals the content to be prose disguised as poetry, most often found in free verse. Even free verse requires the use of some poetic techniques, and a sense of prosody, to distinguish it from prose; the poet simply has more choice about which ones to use.
- YAWN. Bad poetry is almost always boring. Go watch grass grow to put some excitement in your day.
When you encounter bad poetry, identify it as such. It's okay for people to write bad poetry; it's not okay for people to obscure good poetry by falsely claiming that bad poetry is good. (Note that I'm referring here to poems with identifiable flaws, rather than to unfounded disputes over personal taste. Not everyone will necessarily like a good poem.) You need not be rude or vulgar, although there are venues that encourage such. You can simply point out the salient flaws. If bad poetry is being hailed as good, it needs to be deflated. In the case of young and/or novice poets, try to be gentle and include praise along with criticism.
The best way of learning how to recognize bad poetry is to practice reading and analyzing it. Some sturdy folks have assembled collections of bad poetry, and related discussions, for public edification:
Bad Poetry Index
The Bad Poetry Page
Very Bad Poetry
The Bad Poetry Seminar
How to Write Bad Poetry
And of course, there is the book that got me hooked on deflating bad poetry: The Stuffed Owl: An Anthology of Bad Verse. Special thanks to Prof. U. Milo Kaufmann for introducing me to that book. Like an owl pellet, it is revolting in a fascinating way. This should be required reading for poets, poetry editors, teachers of poetry, and anyone else serious about working in the genre. Consider it a field guide to monstrosities.