Brandes' point of view
Yes, it really is that simple. With 50 years’ experience as a value investing firm, Brandes would point out that “simple” is not the same as “easy.” Determining a reasonable estimate of the value of a company requires good access to information, detailed analysis of fundamentals, and a broad understanding of the industry and economic environment in which that company operates. It’s not easy, but it’s what we aim to do across a broad universe of companies worldwide. When that value has been estimated, only then is it simple(r) to buy it if it’s at a sufficient discount.
Source: Margin of Safety: Risk Averse Value Investing Strategies for the Thoughtful Investor, Seth A. Klarman (HarperCollins, 1991)