Microsoft is a classic American story. If you want to know why Microsoft is the best in some people’s minds, it helps to start with that. But two people can look at the same set of facts about Microsoft and come to very different conclusions. That makes Microsoft interesting to follow, but at times confounding.
Microsoft’s story is basically the story of a string of successes, in sequence. The details matter, but in a nutshell, people’s opinion about Microsoft is generally shaped by their opinion about that success.