Worth adding that the ability to work hard and delay gratification is a privilege, Self-control seems to be 60%[1] heritable (and let’s not forget that people also don’t choose in which environment they grow up which probably accounts for the other 40%)
In a way, it’s privilege all the way down.
https://www.sciencedirect.com/science/article/pii/S0149763418307905
This approach reminds me of the six-sigma manufacturing philosophy which was very successful and impactful in improving manufactured products quality.