it is the classical principal-agent dilemma that we face in society since the point in time we started delegating individual tasks to individuals, for any individual will carry the seeds of greed and egoism in it in varying degrees. thus there will always be a conflict of interest for evolutionary reasons.

over the millenia we've developed mechanisms like the division of power (checks & balances) for governments and the board system for corporations.

what I want to say with this is that if organizational stewardship is not working, it's most likely a flaw in the structure of the system (and/or the processes), and my instinct would tell me to investigate if the right amount & scrutiny in terms of checks & balances is in place.