One of the more consequential findings in the cavalclade of research that started to filter then flow from univerisities over the past several decades was that the act of paying attention - simple willpower - has a cost. That calories and sleep and the point in the day happen to control how much attention you an devote to one thing or another was a surprising finding. Willpower is depletable, and far from infinite.
I don't know the exact thinker who first extrapolated that this impacts heavily on poverty, but it was a genius connection. Alex Tabarrok points here to a study showing that because lower income people have to devote more attention to a larger number of mundane decisions - for example if I buy this winter coat then can I afford a segment of this weeks shopping? - this means that less willpower is available for the consideration of other tasks, which means that decisions with more distant payoffs (insurance, education) are not given due attention, leading to a confused circle.
A wealthier person when faced with such a problem does not have to devote mental energy to the basic trade off, as Tabarrok says in connection with an unpredicable brake job on his car:
'Compared to a poorer person I benefited from my wealth twice, once by being able to cover the expense and again by not having to devote cognitive resources to solving the problem.'
The correct allocation of working cash through ones life is an exhausting task when income is constricted, and one can see how these little decisions can build up and deplete the general pool of mental energy. This is one of the benefits of Britain's NHS. By not having to waste time thinking about that aspect of life, the population as a whole, and the poor disproportionately, benefit. Whereas in America there is a localised list of plans and benefits, all with vague and hidden and non-up-front costs, and the population must engage in a constant battle of willpower with suited spreadsheet crunchers to get a decent plan in an emergency. Choice has a cost, a serious willpower cost.
And this has implications for economic development as well, especially when added to the more basic problem of insuffient calories to think and go about ones day. The opportunity cost of all these decisions can needlessly constrain a life, and choke an economy.