Mohammed Yunis came up with a good idea: Give small loans to people who don’t have access to capital. A high percentage of the world’s population lives at a subsistence level. They spend all they make on food, and have none left for an “investment” that might make their microbusiness more profitable. If you could buy more bananas in the first place, your profit would be higher. If you could buy a cart, you could bring more bananas back to your village to sell than you’ve been able to carry yourself.