Why does anyone pay attention to the ratings agencies?

[TwoPenniesEarned]

If Moody's or S&P suddenly downgrade another country's sovereign debt, why is it newsworthy? We established in 2008 that these agencies don't give a AAA based on credible criteria but rather because they were bribed. Why does anyone think this has changed? What gives a credit rating more worth today than it had in 2008?

[avidbrandy]

because it's how it's always been traded. It's always been something that companies see and implement into the wonderful computers that now account for 90% of trades in the market.

It's like why Oil is going up isn't it? Oil goes up because of there being more oil going through the pipeline in Oklahoma, because it's perceived as more demand. Even though that makes absolutely no sense right now; the oil price is going up because there's more supply right now. But it used to make sense so everyone still trades on it to make a quick buck.