Why did the financial crisis cause so many people to lose their jobs?

After the bank invests, it cannot recover the investment funds, so it has to transfer the money from other places and pass it on to the company that borrowed the loan. The company that borrowed the loan cannot afford to repay it and goes bankrupt. This leads to the loss of employees of the company and a chain reaction. , because some companies went bankrupt, some orders were cancelled, and other companies that relied on these orders were also affected. They either closed down or laid off employees. It was like a snowball, and the scope of the impact was getting wider and wider. It led to an economic depression and a large number of unemployed people.