Two rich businessmen are walking as friends in a park.
The first businessman whos name was Joe discovered a pile of dog роор on the sidewalk. He then told the other businessman, Jack, that if Jack ate the pile of роор he will give Jack a billion dollars. Jack agreed, so he ate the pile of роор and gained a billion dollars.
Later, Jack saw another pile of роор on the grass. He told Joe that if he ate it, he will give back the billion dollars. Joe agreed because he didn't want to lose the money, and he did.
Much later, the two men were all crying their eyes out because they both ate a pile of роор and didn't gain a cent!