While CEO, Pinchai's and Cook's companies increased in value by 2.7x and 8.6x respectively, so they must be doing a very high quality job at what they were selected for.

Yes but many people would say (and that's my opinion as well) that they achieved that by resting on what was already working and minor/logical improvement of prviously mapped steps, and that that would be caught like a deer in headlight by the need to perform a massive change to adapt.

They're extremly good (better than most) at keeping the machine well oiled and maintained to ensure it performs as best as possible, but when the machine won't be able to do the job anymore they will have a hard time foreseeing it or finding the new solution.

Just like what is happening at Intel.