From an economist's perspective, conscientiousness is correlated with income. This is not really surprising, since people who bust ass tend to do well in life. I don't know whether IQ or C is more highly correlated with income in a free market economy, but I would actually guess conscientiousness.
- Markets: Rich/Nice vs Poor/Mean
- Conscientiousness and poverty
- Rothbard on poverty
- What happens if you give a homeless person $100,000?
All of this raises the unseemly question: are you saying that it is the fault of the poor that they are poor? Yes. With important mitigating distinctions. Social and cultural factors have a huge contribution as well. Being a Catholic, I tend to see things like this as both/and rather than either/or. In a world of easy credit and payday loans, it is not even a little surprising that people who consistently focus on the short-term will be disproportionately concentrated on the bottom. Since this trait is heritable in the broad sense, it is also not surprising that poverty persists across generations.
But that being said, not every set of social arrangements is equally difficult for those with a lack of conscientiousness to negotiate. Sometimes the system really does hold you down. Some cultures glorify an ethos of eat, drink, charge, and be merry, and others set their face against manifest improvidence. I have it on good authority that poverty is not actually solvable, so I would rather focus on what makes life better for everyone in their broad diversity of talents and personalities than try to amend a self-perpetuating inequality.