Actually entrepreneurship is ALL about market opportunities and ideas. All you do is maximize all the odds and leverage everything you have for a win. Winning is all that matters, and winning as big as you can.
Now if you want to take on a big challenge, change the world, and build something magical, you can and you should. However none of these are required, and each of these is more likely to be a problem.
Now if you want to take on a big challenge, change the world, and build something magical, you can and you should. However none of these are required, and each of these is more likely to be a problem.