Two large changes for better in Microsoft:

1. 2006 Bill Gates stepped down as a Chief Software Architect

2. 2014 Satya Nadella became CEO after Ballmer.

Gates was good CEO but he was not a good Chief Architect. He had the knowledge, the intelligence and skills, but he had no ability to do good high-level choices. Chief Architect needs to know when to sacrifice in details to get the whole slightly better.

Microsoft is not known for innovation,but they should have been able to do gradual refinement better under Gates. Microsoft was really starting to crumble under the completely unprincipled approach to large scale architecture.