The most influential promoter of Steve Jobs' indispensability, of course, is Steve Jobs. But another person who is very much with that program is the one executive who has actually filled in for Jobs as CEO. That would be Tim Cook, Apple's chief operating officer and its interim chief executive for two months in 2004, when Jobs was recovering from cancer surgery.

Tim cook arrived at Apple in 1998 from Compaq Computer. He was a 16-year computer-industry veteran - he'd worked for IBM (IBM, Fortune 500) for 12 of those years - with a mandate to clean up the atrocious state of Apple's manufacturing, distribution, and supply apparatus. One day back then, he convened a meeting with his team, and the discussion turned to a particular problem in Asia.

"This is really bad," Cook told the group. "Someone should be in China driving this." Thirty minutes into that meeting Cook looked at Sabih Khan, a key operations executive, and abruptly asked, without a trace of emotion, "Why are you still here?"

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