In this essay, I want to tell readers about two of the last century’s big and fascinating business failures. But first, some related insights. In her 2008 commencement address at Harvard University, “Harry Potter” author J. K. Rowling famously asserted, “It is impossible to live without failing at something, unless you live so cautiously that you might as well not have lived at all—in which case, you fail by default.” So many well-known businesspeople failed before they succeeded or failed at something after they succeeded. Learning from failure is a cardinal rule of entrepreneurship. The difference between a bad entrepreneur and a good one is not failure, but rather, allowing failure to sink you or to teach you. The motivational speaker Dennis Waitley said: “Failure should be our teacher, not our undertaker. Failure is delay, not defeat. It is a temporary detour, not a dead end. Failure is something we can avoid only by …