If I were to speculate I'd say it's because they don't ship things until they are finished. I'm sure a lot of the polished launches we have seen have been late

If I were to speculate I'd say it's because they don't ship things until they are finished. I'm sure a lot of the polished launches we have seen have been late by 6, 12 or 24 months. If the market isn't ready, the product doesn't ship. If the technology isn't ready (say, a high enough resolution VR display) to create a wow product then the product doesn't ship. I think it takes a great organization to not "accidentally" ship bad things. You need to prevent bonuses, egos, sunk costs, and self-deception from shipping something bad prematurely.