The housing collapse and mortgage meltdown were caused by loose lending standards that allowed people to take out loans without verifying income, employment, or creditworthiness. Low interest rates fueled demand and further inflated home prices. Both borrowers and lenders were greedy, as many took out loans they couldn't repay in order to speculate on further home price appreciation. Risky subprime and option ARM loans, in particular, caused the most problems due to their volatile terms. In contrast, VA hybrid loans maintained stable underwriting standards and did not contribute to the crash.