Invested: Changing Forever the Way Americans Invest by Charles Schwab (2019)
The book was useful in two ways. The life of the founder, Charles Schwab, shows that a successful business starts with addressing a clear customer need (high brokerage fees by established players), and success comes from a constant focus on helping the customer (similar to ideas expressed by Amazon's founder Jeff Bezos). Schwab saw this market opportunity because he was a customer of one of the big established traditional brokers himself and wanted to invest directly in the market at much lower fees.