Because the banks had to be closed down and they had no way to get what they needed.
A large number of families lost their savings since nearly half of the banks collapsed, Unemployment rate escalated, homelessness was raging, house prices plunged 30%, international trade nearly collapsed, and the like.
The Great Depression represented the worst economic downturn in the history of the industrialized world, spanning from the stock market crash of 1929 to 1939.
Americans were unemployed and nearly half the country’s banks had failed.