1. Costco's efficient business model and high customer loyalty drive consistent shareholder value, but its current valuation is too high for a buy rating. 2. Despite robust growth and resilience to economic conditions, Costco's forward price-to-earnings ratio implies a low earnings yield for a couple of years, making it less attractive for new investments. 3. Potential growth paths include international expansion and e-commerce, but challenges in adapting the business model to new regions exist.