Business
A service can treat most of its poorest customers for free and still pay its own way if it keeps prices low and sees far more people. The many paying patients, at a cost far below rich-world prices, cover the ones who cannot pay. The book reports this working without grants or donations.
After being refused loans, the founder chose never to borrow and set the venture up as a trust. Any money left over after running costs went straight into expanding the work. This tied growth to what the work itself earned, instead of to lenders or investors.
Some of the founder's most important decisions came before he had any reasoned case for them. He held that reason is a poor tool for finding truth. Choices made this way often paid off 5, 10, or 20 years later.