Banks create money out of thin air, fractional reserve banking. When the banks go bust the Central banks save the debts. People speculate in house prices, peopl

Banks create money out of thin air, fractional reserve banking. When the banks go bust the Central banks save the debts. People speculate in house prices, people loan more for their new home than their old one, new debts are created. It goes on until there is a bust in the market, either financial shock, or price discovery that the loans are not sustainable.