What the Enron executives didn't count on was that they would be exposed before they could fully cash out and that they would be held criminally liable for their actions in the same manner that a bank robber doesn't count on getting caught before they can get away with their money.
Their intention was manifestly not to run the company into the ground - if that were the case they would not have had 95+% of their personal fortunes invested in Enron stock.
What they were hoping to do was to sell the inflated investment vehicles inside Enron off to other companies in order to boost Enron stock.