If you decide that you're going to do only the things you know are going to work, you're going to leave a lot of opportunity on the table.

It’s very important for entrepreneurs to be realistic. So if you believe on that first day while you’re writing the business plan that there’s a 70 percent chance that the whole thing will fail, then that kind of relieves the pressure of self-doubt.

Though we are optimistic, we must remain vigilant and maintain a sense of urgency.

If you make customers unhappy in the physical world, they might each tell 6 friends. If you make customers unhappy on the Internet, they can each tell 6,000 friends.

Our point of view is we will sell more if we help people make purchasing decisions.

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.

Determine what your customers need, and work backwards.