These investors bought a high-quality company at a massively discounted valuation.Costco Wholesale (COST 0.19%) has long remained one of the most successful retailers in the U.S. and much of the world. However, this did not make the company invulnerable 15 years ago during the financial crisis.At that time, its rapid growth briefly turned negative as consumers reined in unnecessary spending. Nonetheless, it was also a retailer that recovered quickly as the crisis receded. Additionally, the improvements led ...