How did the Roaring Twenties contribute to the cause of the Great Depression?

The Roaring Twenties had people making more and more - - so much so that there was an unnecessary amount of items. There had been credit that led to people buying items they could not have bought without credit. Everyone was buying, for example, toasters although it was useless on credit and paying little by little. When this was happening, the economy was affected and this led as one of the greatest factors of the Great Depression.