Warren Buffett's partner Charlie Munger spent most of his life emphasizing a principle: discipline, patience, and smart decision-making. But few topics could make his eyes light up like Costco. In his last major interview, Munger explained in detail why this warehouse retail giant became one of his favorite business case studies. He believed that Costco's operating model embodies true business wisdom — by establishing extremely rigorous cost control, an unwavering pursuit of member value, and a long-term perspective, it has built competitive moats that are difficult to replicate. This way of thinking deserves every investor's reflection: the most profitable businesses often come from the most straightforward logic.