How did the unstable economy in the late 1920's contribute to the Great Depression?

The unstable economy in the 1920s led to the Great Depression because of the stock market crash of 1929, bank failures, and reduction in sales. The stock market crash is where stock prices fell and people all across the country lost money.

Production far outpaced demands, wealth was unevenly distributed, boom in stock market, prices were based on borrowed money and not real value.