Everything Always Takes Longer Than You Think

Photo: Alex Teuscher/Getty Images

Projects at work, around the house, and whatever it is the construction workers have been loudly doing across the street from me for months now: Everything always seems to take longer to complete than anyone expects. If you’ve ever set a deadline for yourself, and then watched in alarm as the set day came and went and the thing you’re working on somehow still isn’t done, at least you can rest assured that it’s not just you.

This tendency, in fact, is so common it has its own name — perhaps you’ve heard of the planning fallacy, a cognitive bias identified by the dream psychology team of Daniel Kahneman and Amos Tversky in 1979, which holds that people tend to underestimate how long it will take them to get stuff done. A good explanation of this can be found in Mindwise, by University of Chicago psychologist Nicholas Epley. In it, the author asks the reader to conduct a little self-experiment; all it requires of you, if you’d like to play along, is pen and paper, or perhaps a new Google doc. First, think of a task that you’d really like to finish in the next few weeks. Now, write down these three dates:

• The date by which you will have finished the aforementioned task.
• The date you’ll be done if everything goes right.
• The date you’ll be done if everything goes wrong.

And then, the sad reveal: Not only is it likely that you will miss the dates for your best-case scenario and your realistic scenario — chances are high that you’ll blow past even your worst-case-scenario deadline. Epley cites a classic study, in which professors of psychology asked their undergraduate students these three questions, specifically about when they might finish their theses. Realistically, the students said it would likely take them 34 days, on average, to finish. Best-case scenario: 27 days. And worst-case: 49 days. In the end, they took 55 days on average. “Even worst-case scenarios tend to be overly optimistic,” Epley notes.

These are averages, which suggests some people probably did hit their target dates. Also, these are undergrads, and I would hope your — and my — time-management skills have improved since college. Then again, I thought I would finish this post last week. (I write this stuff for me, not just for you, dear readers.)

If optimism helps create the planning fallacy, perhaps a little dose of pessimism will help eliminate it. In a Science of Us column published earlier this year, Brad Stulberg advises trying a “premortem”: Imagine you’ve already gone and missed your deadline. What happened? What went wrong? Be realistic, and plan accordingly. “When you force yourself to become aware of all that could go wrong,” Stulberg writes, “you become more likely to take the necessary steps to ensure that things go right.”

Everything Always Takes Longer Than You Think