Once upon a time in a village, a man appeared with a plan and announced to the villagers that he would buy pigs for $10.
Hearing this, the villagers, knowing that there were many stray pigs around, went out to the forest and started catching them. The man bought thousands of pigs at $10 and as the supply started to diminish, the villagers stopped their effort of searching for pigs.
The man further announced that he would now buy PIGS at $20. this renewed the efforts of the villagers and they started catching pigs again, sold them to the man. Soon, the supply diminished even further and people stopped their effort again.
The offer was increased to $25 and the pigs were bought again and the supply diminished again. Soon, there were no pigs to catch.
The man now announced that he would buy pigs at $50 and left for the city, leaving behind his assistant who would buy on his behalf.
Since, there were almost no stray pigs to catch and sell, the villagers gave up the effort of even searching.
However, in the absence of the man, the assistant showed the villagers all the pigs that have been bought so far and told them that he would sell them the pigs for $35 and when the man returns form the city, they could sell it to the man for $50.
The villagers squeezed up with their savings and bought all the pigs till there were no pigs left.
The villagers never saw the man or the assistant ever again.