Michael Lopp, for Rands in Repose, wrote Someone is Coming to Eat You, a brilliant article on success and competition, well worth reading.

Apple’s current biggest competitor is itself, and I think Steve Jobs learned this the hard way - from the sidelines. When he returned, one of his first hires was a gentlemen named Tim Cook, and while Tim Cook holds a degree in industrial engineering, he is not an engineer, a designer, or a poet. Tim Cook is an execution machine and he exists at Apple to enable them to pull off one thing - the iPod Mini moment.