Successful entrepreneurs are more likely to be smarter than less successful entrepreneurs, but the most successful people in any field are more likely to belong to the set of "super smart."

I think to some degree, "super smart" people are less likely to be interested in entrepreneurship because they find the business aspects of entrepreneurship dull. (I don't think you could classify me as "super smart," but I belong to the set of people bored by business.) Some people want to spend all their time solving problems that they find fascinating. Taking less financial risk -- and consequently reaping fewer financial rewards -- might be a worthwhile trade-off if it means you can spend all, or at least more of, your time tackling problems you find fascinating.