Anyone in business, of any kind, that hasn't read Clayton Christensen's "The Innovators Dilemma" is eventually doomed. John Gruber of Daring Fireball points out this weakness in the Washington Post's article sympathetic to Ballmers demise...
Seems to me Lee is in fact arguing that Microsoft’s decline was exactly Ballmer’s fault. His refusal to allow any other projects within Microsoft to disrupt Windows or Office made it inevitable that such disruptions would come from other companies. Christensen’s The Innovator’s Dilemma was itself disruptive to standard business practices, but it came out in 1997. Did Ballmer not read it? Did he think Microsoft was somehow immune?
Via Daring Fireball