Visitors to a scenic mountain village were often amused by the village idiot. When offered a choice between a shiny 50-cent piece and a crumpled $5 bill, he would always happily choose the half-dollar. The bill was worth ten times as much, so why did he never choose it?
The so-called village idiot was smart enough to realize that as long as he kept choosing a 50-cent piece, people would keep offering him the choice. If he took the $5 bill once, the stream of coins would stop rolling in.