How Microsoft Lost the API War

Microsoft's crown strategic jewel, the Windows API, is lost. The cornerstone of Microsoft's monopoly power and incredibly profitable Windows and Office franchises, which account for virtually all of Microsoft's income and covers up a huge array of unprofitable or marginally profitable product lines, the Windows API is no longer of much interest to developers. The goose that lays the golden eggs is not quite dead, but it does have a terminal disease, one that nobody noticed yet.

Spolsky, Joel. Joel on Software (2004). Articles>Technology>Software>Microsoft Windows