Large corps may produce mediocrity, but the issue for MS is not so much that - they have talent, and are operationally effective.

I think large corps fail to grasp industry pivots - and they keep doing 'more of same' - failing to take risks on new, emerging concepts.

Part of this is 'baked in' - large, incumbent entities have more to lose than to gain by innovation.

Protecting MS monopoly is easier than taking the risk of heading in a new direction that does not pan out. Very, very few companies can do it well.

Amazon did a great job with AWS - but that was a spin-off of something they already used internally, so it had at least one 'satisfied real world customer' in a way.

Also - consider Apple without the iPhone. They just would not be what they are. The iPhone was a rare win, and it had a lot to do with leap-frogging BlackBerry - who created the market demand for data services. Were it not for BB making ridiculous amounts of surplus profits, Jobs would have not been able to justify to himself a $200M investment in the iPhone. Of course - MS should have seen this and acted more aggressively on creating a better experience - they missed it.

In the end I think Cook came up through the ranks of Ops, and is a trusted maintainer of the system. Ballmer is a loud, boorish Trump-like figure who I don't think was very liked.