Solve the surface first
The surface is important. It's where your product or service meets customers. Human beings are complex and fickle, so it's impossible to predict how they'll react to a brand-new solution. When our new ideas fail, it's usually because we were overconfident about how well customers would understand and how much they would care.
Get that surface right, and you can work backward to figure out the underlying systems or technology. Focusing on the surface allows you to move fast and answer big questions before you commit to execution, which is why any challenge, no matter how large, can benefit from sprint.
I'm convinced that about half of what separates the successful entrepreneurs from the non-successful ones is pure perseverance. It is so hard. You put so much of your life into this thing. There are such rough moments in time that I think most people give up. I don't blame them. Its really tough and it consumes your life. If you've got a family and you're in the early days of a company, I can't imagine how one could do it. I'm sure its been done but its rough. Its pretty much an eighteen hour day job, seven days a week for awhile. Unless you have a lot of passion about this, you're not going to survive. You're going to give it up. So you've got to have an idea, or a problem or a wrong that you want to right that you're passionate about otherwise you're not going to have the perseverance to stick it through. I think that's half the battle right there.
[Many people] think it means accept failure with dignity and move on. The better, more subtle interpretation is that failure is a manifestation of learning and exploration. If you aren’t experiencing failure, then you are making a far worse mistake: You are being driven by the desire to avoid it. And, for leaders especially, this strategy — trying to avoid failure by out-thinking it — dooms you to fail.
Perfection is achieved, not when there is nothing more to add, but when there is nothing left to take away.
Focus is saying no to 1,000 good ideas.