Er, not really. The real reason is not 'shit happens' but the cozy arrangements that boards and management have put in place; traditions solidified by mutually-beneficial remuneration contracts. Members of the board used to be 'management' in their previous life, and management aim to be board members in the next.
> Here's the thing: dollar-for-dollar, most senior executives are better off quitting ("retiring"),
> unless some divorce, gambling addition or coke habit has eaten away all their savings.
How true, I am not sure. Maybe you are right about older CEOs. But most CEOs are not willing to retire. MBA schools meanwhile, pump out dozens of whippersnappers. With pay differences being huge between CEO and 'CEO-2' levels , there are ample alternatives to highly paid CEOs -- 'cheaper' CEOs (as in the past), governing councils instead of CEOs, co-CEOs, even rotating CEOs. Now to be sure, not all these are good ideas for all companies. But one - 'cheaper CEOs' - for certain is an idea that worked quite well in the decades past.