The standard way to model the time factor in cost-benefit analyses is to discount the future. For most people, gains in the present are worth more than gains in the future. But time doesn't have to matter to us. Some adults, when they have children, for example, begin to exist in a timeless universe, one where they live just to monitor the growth of their children. Their main costs and benefits have been subsumed into their spawn. Should we go on vacation or not? It doesn't matter, because their children are living out their lives. Whether a decade or two passes by for the parents, it's no bother, since it's the arc of their children's story, something they can't control, that matters.
So the rationalist would find another function, a global discounting of costs and benefits. But, as the layers of discounting functions increases, so does the risk of overfitting, thus rendering analysis meaningless. Sometimes, there are zero costs, zero benefits, over zero time, leading to division by zero somewhere, making the whole calculus undefined.
Rationality is a ritual, one that involves light, vague estimates of costs and benefits
They're so light, that one wonders if they can even be called rational. For example, when you ask for help and someone volunteers it, neither party is really measuring cost-benefit because the stakes are so low. Rather, all our actions are just a matter of drives and culture. Likewise, in the case of voting, it's not a rational decision for most of the electorate.
The Usefulness of Accuracy
Accurate statements aren't necessary, or even useful. For example, if your child gets mugged while walking down an alley in a rough neighborhood, then according to law and accuracy, the cause of their mugging was the mugger. Many other people have walked down that alley in that neighborhood and not gotten mugged. But you would still scold your child until they promise not to walk down that alley again, because that's what's most likely to prevent them from getting mugged in the future. You can cause your child to be less mugged in the future by blaming them for their mugging in the past.