When you start a company, it's more an art than a science because it's totally unknown. Instead of solving high-profile problems, try to solve something that's deeply personal to you. Ideally, if you're an ordinary person and you've just solved your problem, you might have solved the problem for millions of people.
Every day I would wake up and think, 'Today is another missed opportunity to do something important.' After enough days like this, you start feeling like you are getting old, even when you are relatively young. We are all natural entrepreneurs, and being manacled to a desk job is not for us.