The only useful information about the market will be what I create through expeditions into the market, through testing and probing, trial and error, by selling real products to real people who pay real money.

How can you make sense of the future when you only have data about the past?

I was lucky enough to build on the work of a number of people who had already run laps around this theory-building track. The original classification scheme, years ago, distinguished radical from incremental change. The theory said that established firms managed incremental change well, but would be expected to founder when their industry encountered a radical change.

It is a company's customers who effectively control what it can and cannot do.

I've concluded that the metric by which God will assess my life isn't dollars, but the individual people whose lives I've touched. I think that's the way it will work for us all. Don't worry about the level of individual prominence you have achieved; worry about the individuals you have helped become better people.

In a large successful company where your power base as CEO isn't all that secure, it's hard for a CEO to pursue a truly disruptive strategy.

One reason there are so many short-lived management fads is that their prescriptions were derived and advocated in precisely this way. So managers read about a fad and try it, find that it doesn't work, abandon the effort, and move on to the next thing. In reality, it is usually the case that the faddish prescription was indeed sound advice in certain circumstances, but actually was poor advice in other circumstances.