Here are the culprit
Wall st - Gave unrealistic valuations for IPO with zero regards to the inherent business risk with ZNGA's shaky business model
Mr. Pincus - Unloaded bulk of shares at IPO price showing no confidence in his own company
Employee confidence - Once the CEO showed no confidence, the employees who came looking for a huge payout jumped out of the sinking ship.
I think Wall st ipo promoters and CEO should be held accountable for this disaster