Why might a bank run out of money and not be able to cover their customers?

Banks invest their money in items, and the stock market. could crash, the market could go down, or the people wouldd. just get uninterested in the item. Then, not wanting to purchase it or support it, banks run out of money. This can also happen because many people remove themselves ffrom the bank's membership and thus the bank can no longer invest or give customers back.

Cause they lost all there money