Except in very narrow cases, where there's breakthrough science that needs patent production, worrying about competitors is a waste of time. If you can't out iterate someone who is trying to copy you, you're toast anyway.

Customers don't care how much time something takes to build. They care only if it serves their needs.

This is one of the most important lessons of the scientific method: if you cannot fail, you cannot learn.

Entrepreneurship is not really building a product, it's not having an idea, it's not being in the right place at the right time. It's fundamentally company building.

What if we found ourselves building something that nobody wanted? In that case what did it matter if we did it on time and on budget?

In my first start-up, I had an initial advertising budget of $5 per day total. That would buy us 100 clicks per day. At $5 per day, marketing people scoffed and said that is too small to matter. But if you think about it, to an engineer, 100 real humans everyday giving your product a try means you can really start improving.

As an entrepreneur, I knew that if my company failed, I could always try again. So I often felt that the only real risk of true financial ruin came from the possibility of a serious illness that either exceeded my insurance plans lifetime limits, or was not covered due to rescission.