Who needs rating agencies?

Warren Buffet certainly does not need them as he prefers to do his own analysis. We also suggest that investors do their own cooking. The only instances that makes ratings useful for investment decisions happen to be the situations where the consensus and/or ratings appear to cause a mispricing in the underlying security that allows a canny investor to benefit by taking the opposite side of the trade. As long as ratings are based on hard facts, usually numbers found in company accounts or data in national statistics, it is a simple matter of arithmetic to deduce the risk associated with a particular issuer. Where ratings rely on judgement calls they become highly subjective and should not be worth more than any other market opinion. Conflicts of interest exist when ratings agencies are given access to non-public information. As it is not possible for other investors to verify the information themselves, some lazy or naive investors get seduced to put excessive reliance on ratings decisions. This risk is exacerbated when laws or customs give ratings an official blessing - for example by requiring collateral posted with the European Central Bank to be of a certain credit quality testified by a rating.