The real issue is that ERA does not answer the relevant questions about pitching performances. It doesn't answer either "Who pitched the best?" or "Who will pitch the best?" That is, whose pitching performance was most valuable to his team? Whose performance, based on available data, is likely to be the best going forward? ERA's weaknesses when it comes to providing these answers aren't difficult to find, and it's for these reasons that we use superior statistics. . .