Percentage margins don't matter. What matters always is dollar margins: the actual dollar amount. Companies are valued not on their percentage margins, but on how many dollars they actually make, and a multiple of that.

If you look at academic studies, you can see that stock prices are most closely correlated with cash flow. It's such a straightforward number. Cash flow is what will drive shareholder returns.

The smartest people are constantly revising their understanding, reconsidering a problem they thought they’d already solved. They’re open to new points of view, new information, new ideas, contradictions, and challenges to their own way of thinking.

Web 1.0 was making the Internet for people, Web 2.0 is making the Internet better for companies.

There are a whole bunch of people who don't like to shop. But there are also people, maybe, who even do like to shop but are very time pressured. And so shopping online can save people time.

If you're not stubborn, you'll give up on experiments too soon. And if you're not flexible, you'll pound your head against the wall and you won't see a different solution to a problem you're trying to solve.

The great thing about fact-based decisions is that they overrule the hierarchy.