Warren Buffett's partner Charlie Munger has emphasized a principle for most of his life: discipline, patience, and smart decision-making. But few topics can make his eyes light up like Costco. In his last long interview, Munger explained in detail why this warehouse retail giant has become one of his favorite business cases. He believes that Costco's operating model embodies true business wisdom — through extremely strict cost control, a relentless pursuit of member value, and a long-term perspective, it has built an insurmountable competitive barrier. This way of thinking is worth deep reflection for every investor: the most profitable businesses often come from the simplest logic.