It's primary a function of time preferences. <i>Ceteris paribus</i>, men prefer things that can be consumes right now rather than later.<p>Everyone knows that exercise is good for you, credit card debt is bad, etc. However, most people succumb to shot term temptation, rather than long term gain.<p>It is like the marshmallow experiment conducted by Standford university.(<a href="http://www.newyorker.com/reporting/2009/05/18/090518fa_fact_lehrer" rel="nofollow">http://www.newyorker.com/reporting/2009/05/18/090518fa_fact_...</a>)<p>Most kids succumb before they can get the second marshmallow. However, those that wait these long few minutes will get two of them.<p>If a man will have a low time preference, in general, he will be more wealthier than a man with a high time preference.