A Motel 6 on a nondescript stretch of First Street near the San Jose airport holds a special place in the history of management thinking. It was there, nearly 13 years ago, in the no-frills accommodations he could afford on a doctoral student's stipend, that 39-year-old Clayton Christensen hatched his powerfully unsettling idea.

A onetime White House Fellow, a former assistant to two U.S. secretaries of transportation and Rhodes Scholar, Christensen had just bailed out of the high-tech-materials manufacturing company he cofounded. A question had taken hold in his mind, and he couldn't help but follow its trail. As the chairman and president of a company that served the then-booming minicomputer industry clustered around Boston's Route 128, Christensen had watched a familiar pattern play out. The novel solutions, rapid growth, and marketplace wins of these companies were invariably credited to the management team's extraordinary vision, capabilities, and tactics. And when those same companies inevitably foundered, those once-celebrated executives were blasted for ineptitude.

"It was as if everybody clapped their hands and suddenly the managers who had been so revered were vilified," recalls Christensen, with a sad shake of his head. "The dumb-manager theory of business problems just didn't hold water for me. There had to be a deeper reason why smart people would make decisions that lead to failure. I wanted to know why. Why is it so hard to sustain success? Why do good companies fail?"

Those questions led Christensen to the petri dish of San Jose's disk-drive industry and to a Harvard Business School doctorate. The answer was something Christensen called "disruptive innovation." Successful companies, he found, tend to swim upstream, pursuing higher-end, higher-margin customers with better technology and better products. These are examples of what Christensen dubs "sustaining innovations." They boost profitability and shareholder returns. They reflect good management. But they can also open a vacuum that disruptive upstarts may rush into with completely different offerings: worse, but cheaper and more convenient products. Dominant companies often ignore these disruptive innovations because they don't interest their mainstream customers. But in so doing, they miss the next great wave of industry growth.

And that, Christensen found, explains why leaders become losers. The good news is, companies don't fail because of bad management. The bad news is, they fail because of good management. "By doing what they must do to keep their margins strong and their stock price healthy, every company paves the way for its own disruption," Christensen says. It was a simple, elegant, and terrifying conclusion: The drive to success becomes a death march.

Christensen immortalized this paradox in a landmark book, The Innovator's Dilemma: When New Technologies Cause Great Firms to Fail (Harvard Business School Press, 1997). The book and the concept of disruption helped fuel both the euphoria and the paranoia of the Internet boom. The fatalism of Christensen's message fed the creeping fear among big-company executives everywhere that they were toast. And it turned Christensen into an unintentional mascot for the startup revolution. For legions of entrepreneurs frothing for their piece of the action, disruption itself became the raison d'etre. Aspiring disruptors excerpted passages of the book verbatim in their business plans. Bill Gates complained publicly that every new-product proposal that came across his desk claimed "disruptive" status. Never mind that Christensen barely mentioned the word in his book--or that, as he puts it, "The most widespread and dangerous misunderstanding of the model is the equation of 'new' or 'breakthrough' with disruption."