A Ponzi scheme is a form of fraud that lures investors and pays profits to earlier investors with funds from more recent investors. The scheme leads victims to believe that profits are coming from legitimate business activity (e.g. product sales and/or successful investments), and they remain unaware that other investors are the source of funds.
from wikipedia.org
Bitcoin wasn't created to generate profit. It isn't a tool to generate money, Bitcoin is deflationary medium of exchange.