Failing is Normal in Silicon Valley
Fear of failure or kind of the inertia that is created can be avoided if you are in the right environment. So in San Francisco literally everyone aspires to be a startup entrepreneur. So failing comes naturally. You will see entrepreneurs who have failed multiple times in the past, that just picks up and goes ahead and does another startup. Some learn from their failures and become extremely successful as an entrepreneur. Having those role models around you and having that kind of social infrastructure makes it pretty easy for people to quit your job at Google, Yahoo, etc and then go straight into a very shaky and a very risky career of entrepreneurship. So I think the social environment is very important.
My Experience
I am the CEO of a company called Goodtime. When we started I made probably hundreds of assumptions and probably 99% were wrong. So how we found out that we were wrong was by talking to customers and we stayed extremely close to them. I even worked for one of them just as a free resource for them, so I could learn the problem from inside out. That allowed us to not pivot completely but to take a detour sometimes to find out which way is the right way to go. So having that kind of flexible mind and talking to customers will give you an idea of what you are actually good at instead of what you assumed you were good at.
Listen to your customers
Being a startup entrepreneur can be very stressful because on a daily basis you are making a lot of decisions. Sometimes doubt settles in and you second guess yourself and your own decisions. The stress level can be really high. I feel like the way to keep your optimization, positivity, and passion for the business high is to listen to your customers, whenever I listen to our customers and how they describe their experience with our product, that really makes my day and keep me going. Also as far as our team I really try hard to let go of control and empower our team to make their own decisions and really trust in their ability to make the right decision for the company. Customers and the team are the two main things that keep me going.