A long long time ago Microsoft was able to compete in the open marketplace. Then Digital Research DR-DOS happened, which was technically superior to MS DOS. In a panic upper management authorized the insertion of codes disabling aps from running on DR-DOS.
Microsoft has never looked back from that key moment. Since then the entire game for MS has all been about leveraging market share rather than quality applications. This is why they can't turn the XBox into profitable division, because as successful as it is in terms of market share, it has not yet become a monopoly. Any other half alive company (no Sony doesn't count) would be raking in the billions with this type of market share. Not so Microsoft