A person should set his goals as early as he can and devote all his energy and talent to getting there. With enough effort, he may achieve it. Or he may find something that is even more rewarding. But in the end, no matter what the outcome, he will know he has been alive.
Swim upstream. Go the other way. Ignore the conventional wisdom. If everybody else is doing it one way, there's a good chance you can find your niche by going in exactly the opposite direction. But be prepared for a lot of folks to wave you down and tell you you're headed the wrong way. I guess in all my years, what I heard more often than anything was: a town of less than 50,000 population cannot support a discount store for very long.