Reason For This Carnage

Market players always try to find reasons for market falls as and when it happens, this time around excessive credit lending to not--trust-worthy people(having very low credit score) in the sub-prime mortgage market is sited as the main culprit behind steep stock market fall as they have de-faulted on their loan obligation. But i say excessive GREED was, is, and will always be the biggest culprit behind every melt down in the asset prices.