OnStartups has a list of 17 pithy insights. Among them:
6. Eventually, your product will need to work and do something useful. No amount of marketing or strategy will get you around this.
7. At the end of each day, ask yourself: Did the product get better for customers today?. If you dont have a good answer, stay up until you do.
8. Until you are profitable, time is working against you. Once you are profitable, time is on your side.