The cost of time

We humans are not good at considering the cost of time in our decisions.

When we make decisions, we weigh financial costs, emotional costs, social costs, energy cost, comfortableness, mental effort, and so on. However, we very seldom factor in the time cost (apart from when choosing a transportation option). Very rarely, we choose an option which costs us more money or energy but saves us time. This behavior holds even when money and energy are abundant: a survey of 800 Dutch millionaires found that only a slight majority spent money on time-saving tasks[1].

The only times when we manage to choose a solution that is more expensive but makes us a time, we do so after a few moments spent imagining how much time it will save us and what we will do with it. It seems like a conscious, effortful simulation in our head is needed for us to take time into account. (Again, this is not valid for transportation choices. In such cases, we appear to value time; however, only in such cases.) When instead we use intuition to make decisions, we seem to neglect the cost of time. Why are our brains wired not to value time?

(A typical counter example I am presented with is: “I buy stuff online to save time.” Yes, people buy stuff online. However, they do so because it is more comfortable: they do not have the dress up and drive to the store. Not because it saves them time.)

Like for so many other questions that start with “Why are our brains wired…”, I believe that the answer lies in evolutionary psychology. Could it be that not considering the cost of time is a positive trait, overall? Let’s imagine how a man that values the cost of time would behave. Probably, he would sleep only a few hours per night: for him, sleeping is expensive. This is bad: the scientific consensus is that, even if we do not exactly know why, sleep is essential for humans. (If you don’t think so, try not to sleep for 48 hours, and then ask yourself what is the single thing that you want to do now.) Let’s continue the thought experiment. That man would also not spend much time in social activities. While spending hours talking, when time is so expensive? This is bad, too. While he would probably have more time to focus on more productive activities, he would end up lonely and isolated: more fragile, in case he would have a problem which would require the help and support of his friends and family.

I argue that the reason humans are not able to intuitively perceive the cost of time is that it is better not to. But wait, aren’t there situations in which it is appropriate to consider the cost of time? Yes, but they are far less and far less important than the ones where it isn’t. Our brain can’t be wired to consider the cost of time only on some occasions, and not in others. Evolution had to choose only one option, and it preferred a brain which does not consider the cost of time.

(By the way, don’t people look happier when they are not in a rush? And don’t people who always keep an eye on their watch look unhappier? Probably, it is wise not to try to add an unnecessary function to what our brain already developed in thousands of years of evolution.)

Notes: 

[1] A. Whillans, 2017, “Buying time promotes happiness.“.