You can invest to create the new growth business while the core business is still growing, because new business units don't need to get big fast. But when the core business stops growing, investing to create new growth businesses becomes impossible.

Year after year after year, people write books about managing innovation or about leadership, for example, without ever going through the pain of saying, "This kind of leadership will cause this result in these circumstances and a very different result in those circumstances." This is academic malpractice of the worst kind.

Breaking an old business model is always going to require leaders to follow their instinct. There will always be persuasive reasons not to take a risk. But if you only do what worked in the past, you will wake up one day and find that you’ve been passed by.

By the time it becomes obvious that a technology will have truly disruptive impact, it is often too late to take action. This is one reason why we are such advocates of using theory to try to analyze industry change. Conclusive evidence that proves that a company needs to take action almost never exists. In fact, the data can fool management, lulling them into a false sense of security.

Almost always great new ideas don't emerge from within a single person or function, but at the intersection of functions or people that have never met before.

Regulatory fiat cannot create a market at a technologically interdependent interface. And by the same token, regulation and so-called monopoly power rarely prevail at modular interfaces between stages of value-added technology.

And if your attitude is that only smarter people have something to teach you, your learning opportunities will be very limited. ... When we see people acting in an abusive, arrogant, or demeaning manner toward others, their behavior almost always is a symptom of their lack of self-esteem. They need to put someone else down to feel good about themselves.