Warren Buffett shares one ‘simple’ tip for evaluating a company before investing and how to avoid costly mistakes

Warren Buffett's investment philosophy emphasizes the 'circle of competence,' urging investors to focus on industries they understand deeply. This approach prioritizes avoiding mistakes over chasing high returns, as demonstrated by his investments in Coca-Cola and See's Candies. By staying within their knowledge boundaries and expanding deliberately, investors can make informed decisions and avoid costly errors.