Orcish poetry is in fact only the third worst in Middle-earth, the second being that of the Fairbairns of the Towers. During a recitation by their poet master, Flumbo the Corpulent, of his poem
Ode to a small piece of green putty I found in my pipeweed one midsummer morning, seven of the audience died of internal haemorrhaging and the president of the Mid-Middle-earth Arts Nobbling Council survived only by gnawing his own leg off. Flumbo was said to be 'disappointed' with the poem's reception, and was about to embark on his twelve-book epic
My Favourite Bathtime Gurgles, when his own major intestine, in a desperate attempt to save life and civilisation, leapt straight up his neck and throttled his brain.
The worst poetry in Middle-earth died with its creator: Vogonwë Brownbark of the Minus Teeth Gazette, in a bizarre calligraphy accident.
With sincere apologies to the late Douglas Adams, the later J.R.R. Tolkien, the unlate Diamond18, the staff of the OED and all writers of English, living or dead.