Tiny Bronco, it's not just that they are short, but that they are off-topic. If a one-word answer is enough to anwer someone's question in a thread and it's on topic, then of course you don't have to type a 500 page essay about it.
EDIT: Here's a good example..
This thread. The two posts by Squall Lionheart in there saying "...plan...." and
especially "Whatever...." are perfect examples of what she meant. The post by Tiny Bronco "Mwhahahahahahahahah!!! Final Fantasy!!!!!!!!" also falls into the same category, despite being 3 words.