Why You Can't Say No

People are more likely to expect a future surplus of time than they are to expect a future surplus of money. Researchers explain why.

By Hara Estroff Marano, published on March 16, 2005 - last reviewed on June 9, 2016

If you're like most people, you say yes to doing more things than you could possibly have time for. Your appointment book is full. But when it comes to actually showing up, you discover you're too busy to do everything you've promised.

The trouble is, you make some faulty assumptions about the future. But not to worry -- so does almost everyone else.

According to North Carolina researchers, you overcommit because you expect to have more time in the future than you do in the present. But then tomorrow becomes today and... yesterday's "yes" becomes today's "damn!" And you find yourself making excuses.

Here's the interesting part. Researchers Gal Zauberman, Ph.D., and John Lynch, Jr., found we are more prone to mistakenly expect a future surplus of time than we are to expect a future surplus of money. We seem to be much more accurate in our money forecasting.

That's because every day's a little different, say the researchers. The nature of time fools us and we "forget" about how things fill our days.

Money, on the other hand, is more "fungible," freely exchanged for something of like kind -- such as four quarters for a dollar bill. "Barring some change in employment or family status, supply and demand of money are relatively constant over time, and people are aware of that," observe Zauberman and Lynch. "Compared with demands on one's time, money needs in the future are relatively predictable from money needs today."

In the lingo of the psych lab, we are prone to a phenomenon known as delay discounting when it comes to our time. Depending on the resource -- time is one, money another -- we exhibit differing degrees of preference to receive a lower reward now rather than a higher reward in the future. We're more likely to think that we'll have more time slack ahead than we do now.

"People often make commitments long in advance that they would never make if the same commitments required immediate action," say the researchers. "That is, they discount future time investments relatively steeply."


Bad enough. But why, you might ask, do we keep making the same mistake over and over again with time? Why do we exhibit such "irrational exuberance" about expected growth in "time slack"? Because time does vary from day to day more than money does, and we are just horrible at "imagining future competition for [our] time."

"It's difficult to learn from feedback that time will not be more abundant in the future because of the irregular ways people spend their time," the researchers write in the Journal of Experimental Psychology. "Although many people may perceive themselves to be quite busy almost every day of their lives, the specific activities vary from day to day. Consequently, they do not learn from feedback that, in aggregate, total demands are similar."

In aggregate. Key words.

We're bad bad bad at learning that future slack time is no greater than present slack time because, given the day-to-day variability in our tasks, we mistakenly think that the activities that compete for our time today are irrelevant to those that will compete for our time in the future.

Let's face it. Most of the time we make a future commitment it's not a life-enhancing opportunity. It's more likely a small professional thing that will provide momentary approval from those we know.

But if something looms ahead that stands a chance of providing a great deal of satisfaction and will linger in memory, go ahead. Make the commitment. The remembrance alone will make it more than worthwhile.