Well, uh, I understand the difference between discovery and invention, but if a person takes the question according to its intended sense... then it's a fine question.
I mean, it's not like the vote channel has a "I disagree with the phrasing" option or anything, and an abstention doesn't contribute much.
Anywho, I figure the wheel's overrated as inventions go (not nearly so overrated as sliced bread, of course). Hard to beat the printing press, which I think has a 9.7 on metacritic.