Investing is about picking the right principles, staying on the right path, and following the right philosophy to perpetually grow the capital. (Location 956)
A good rule of thumb is, if the net margin is over 3%-5% and the returns over 10%-15%, the company is doing something right. (Location 1933)
A good business is a business that has good returns (profits as a percentage of equity or assets, or invested capital, which is total debt and equity), good margins (profits as a percentage of sales), low capital needs (the money needed to maintain and grow the business). (Location 2015)