If you really want to get pedantic about all this, the concept that completion of a Century was the true measure of a cyclist developed when roads were unpaved, and people still road big wheeled bikes.
So unless you're doing your century on a Penny Farthing on dirt roads, HTFU.
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You could fall off a cliff and die.
You could get lost and die.
You could hit a tree and die.
OR YOU COULD STAY HOME AND FALL OFF THE COUCH AND DIE.