Warren Buffett emphasizes the importance of investing in companies with high return on equity (ROE), as it indicates effective management and profitability. He argues that low ROE stocks often reflect underlying business issues that can lead to poor long-term performance. Buffett believes that a strong ROE demonstrates a company's ability to generate value for shareholders, making it a key metric in his investment strategy. He advises investors to prioritize quality over bargain prices, as buying low-quality stocks can result in missed opportunities for growth. Ultimately, Buffett's philosophy underscores the idea that investing in solid companies is more rewarding than chasing low-priced, underperforming stocks.