I built a system simple enough to sustain itself.

It is not really work if you are having fun.

eBay's business is based on enabling someone to do business with another person, and to do that, they first have to develop some measure of trust, either in the other person or the system.

You should pursue your passion. If you're passionate about something and you work hard, then I think you'll be successful. If you start a business because you think you're going to make a lot of money at it, then you probably won't be successful, because that's the wrong reason to start a business. You have to really believe in what you're doing, be passionate enough about it so that you will put in the hours and hard work that it takes to actually succeed there, and then you'll be successful.

I never had it in mind that I would start a company one day and it would really be successful. I have just been motivated by working on interesting technology

Everyone is born equally capable but lacks equal opportunity.

An honest, open environment can bring out the best in people.