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

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.

Focus is scary—until you realize that it only means turning your back on markets you could never have anyway. Sharp focus on jobs that customers are trying to get done holds the promise of greatly improving the odds of success in new-product development.

If the theory accurately predicts what they [scientists] see, it confirms that it's a good theory. If they see something that the theory didn't lead them to believe, that's what Thomas Kuhn calls an anomaly. The anomaly requires a revised theory - and you just keep going through the cycle, making a better theory.

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.

An innovation will get traction only if it helps people get something that they're already doing in their lives done better.

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.