A study disputes the notion that executive pay today is a result of an efficient bidding process for finding and retaining a scarce and valuable commodity: managerial talent.
From my experience, the best senior leaders are the ones that have come-up from within the organization and have a firm grasp of the companies trajectory from having lived within it. We have had some senior leaders come over from other large orgs and they don't do as well.
I know its a "buzz word" but large corporations really do have a "culture" and it can be difficult when someone comes over and tries to swim up-stream as opposed to embracing and working within a given culture.
This is why the CEO's of most org's don't just go around jumping from ship to ship. It's less about pay, more about quality of life and the impact you can have.