This view is challenged by the role of a child in a family. A child is given all of his basic needs by his parents. That includes food, clothing, health care. No decent person expects a child to go out and get a job to buy these things. I child is expected to make his own provisions only for extras, like money for fun events. So if we are to apply your analysis to a child, we would be saying that children, by their very nature, will be lazy and not try to better themselves if we provide for a their basic needs. This is ridiculous. So if it is ridiculous to apply this the children, why is it sensible to apply it to adults? If the basic needs provided truly are “basic”, not “luxurious”, even adults have that same incentive they had when they were children to strive for something better. A better house. A better car. A boat. Travel. This incentive is further confirmed by the fact that those who can excel in life generally do. But if your analysis of human motivation were true, a millionaire real-estate tycoon would stop at a million, since that is enough to meet his “basic” needs, and simply live off the proceeds of his already-successful life. He would not go on to become a multi-millionaire. Yet those that are capable of that generally do.
So we have kids who don’t act as you propose, and moderately successful adults who do not act as you propose. It seems the only people that do actually act as you propose (in your universe) are the poor who are not getting their basic needs met. That leads me to wonder if the flaw is in human nature, or in a uncharitable view of the nature of the poor.