i find there is a reluctance to accept the influence of genetics in the wider population, as, at its most basic level if removes much of our power to influence our lives. What people take pride in, their appearance, their physical attributes, their cognitive abilities and their (positive) personality traits, hard work, determination, loyalty etc, are to a significant amount influenced by genetics. with in those boundaries your ability to achieve at anything, in fact the whole course of your life, is largely out of your control.
there is a nature/ nurture argument about environment, that certainly has influence, but you can't nurture what isn't there in the first place.for instance I've,seen papers that suggest a positive upbringing can add 5 to 10 points to your IQ score , but it cant make you clever if you are stupid. Similarly if you have a natural tendency to be lazy,then that cleverness may not be reward by society, as even a disciplined upbringing won't make you hard working, it will only make you slightly less lazy.