Startups are painful, stressful and at times demoralizing. You need to be a true believer in the vision of what you are doing. You need to passionate about it and love what you’re doing. If you don’t, there is no way you can sustain the hours, stress and disappointment. There’s no way you’re going to be able to convince investors, customers and most importantly recruit a world-class team if you not building something you think is going to change the world.

My advice was to start a policy of making reversible decisions before anyone left the meeting or the office. In a startup, it doesn't matter if you're 100 percent right 100 percent of the time. What matters is having forward momentum and a tight fact-based data/metrics feedback loop to help you quickly recognize and reverse any incorrect decisions. That's why startups are agile. By the time a big company gets the committee to organize the subcommittee to pick a meeting date, your startup could have made 20 decisions, reversed five of them and implemented the fifteen that worked.

Unless you have tested the assumptions in your business model first, outside the building, your business plan is just creative writing.

In a startup no facts exist inside the building, only opinions.

The company that consistently makes and implements decisions rapidly gains a tremendous, often decisive, competitive advantage.

We now know that something between 85 and 90 percent of most software product features are unwanted and unneeded by customers. That is an enourmous ammount of waste of time and money that ends up on the floor.

Greatest risk is not development of new product, but development of customers and markets