"Do what you are passionate about. Without passion, your work is not your love and you can never be your best or be better than others who are running with their passion."
"Do something that you are inherently good or talented at. We all have our relative talents but spending your life doing something that is inherently more difficult puts you at a disadvantage to other more talented people."
"Do something that creates value and can be sold into a market present or future. Creating a widget that nobody but you wants may be self satisfying, but it certainly is not going to make you your fortune nor lead you to personal or professional success."
Here is another quote: "It’s simply a determination to never ever give up. That is the most important element of success: dogged determination. "