I wonder how much game theory there is in having a super sized cash stockpile. Internally apple managers are unlikely to be pressured on R&D costs including salaries, long-term goals. They also are more likely to not be concerned with sunk costs, and can cut projects/features if they don't seem useful to users.

From an external standpoint, competitors have to be aware that "you can't manufacture like apple" and that they will always be forced to make compromises on features/packaging/price in comparison to an apple product.