The Pros And Cons Of Doing One Thing At A Time

One thing at a time

The idea that it’s better to finish your tasks in sequence than to jump around from one to another is very hard to accept, at least for me.

It goes against my ingrained task-juggling habit, which I’ve come to believe is why I can hit my multiple, ever-changing deadlines.

But three researchers — Decio Coviello of HEC Montreal, Andrea Ichino of the University of Bologna, and Nicola Persico of Northwestern University’s Kellogg School — have shown why the sequential approach to completing tasks makes a lot of sense.

Here’s the logic: Let’s say six people simultaneously give you six similar three-day, ASAP tasks, and you juggle them, spending a half day on each in turn.

Although you make good progress on each one as the days go by, you don’t complete any of the tasks until Day 16, when you finally finish the first two. You finish the next two on Day 17 and wrap up the last two on Day 18. But all of the assigners have had to wait a long time, and they’re all annoyed with you for taking so long.

If you attack the tasks sequentially, you finish the first one in just three days, the second in six, the third in nine, and so on. In fact, you complete five of the six earlier than if you had been working on them in parallel (the sixth one wraps at the end of Day 18, same as in the first scenario). So at least two of the assigners are extremely happy and impressed, and overall five of the six assigners are happier than if you had juggled their tasks.

Having published a theoretical paper on this idea, Coviello, Ichino, and Persico went on to study a compelling real-world example: Italian judges who typically get more cases than they can easily handle. Some of the judges were heavy task jugglers, some weren’t. An analysis of the caseloads of this admittedly small sample suggests that there really is an advantage to completing tasks in sequence. The heavy jugglers took longer to complete their portfolios and were less likely to complete their cases in a given time period.


But does that mean I should change my habits and plow through tasks sequentially? I’ve been struggling with this question, and I really don’t know the answer. When I spoke to Persico about the research, he acknowledged that the findings are counterintuitive.

“Even very smart people can be confused about this stuff,” Persico said. His father, a theoretical physicist, was taken aback by it and didn’t quite believe it.

As for Persico himself, the research has changed his way of working, making him more conscious of the value of finishing tasks sequentially. He now tries to work on one research project, or at most two, at a time. He wishes he had known this when he was turning out papers to beat the tenure clock at the University of Pennsylvania — “I would have been more productive,” he says (he got tenure anyway).

A big incentive for juggling, he acknowledges, is that when you’re doing tasks for multiple assigners, you feel pressure from all of them, and sometimes they even lobby you to put their tasks at the top of your queue. You want to be able to say “Ah yes, I was just working on that, and it’s coming along nicely,” rather than “I haven’t looked at it, but it’s on my list.”

Sociopolitical pressure is definitely a factor for me, and although I do eventually hit all (or most, anyway) of my deadlines, I guess I could increase my productivity, at least for certain types of tasks, if I were able to resist that pressure and deal with assignments sequentially. Like for example if I had a half-dozen short-duration, relatively uncreative chores such as responding to article proposals, I can see how it might be better to get them all done sequentially, even if it meant that some would be put off for a while.

And then there’s the interruption issue. I’m well aware that sustained effort on a given task allows you get into that flow state of contented absorption in which the rest of the world falls away. Sustained effort leading to task completion allows you to achieve psychological closure, a human need so deep that, as one study showed, interrupting people in a task, especially at a climactic moment, stimulates a need for closure that spills over and makes them more decisive in unrelated tasks.

OK. But I have a sense that I get something positive out of task juggling, something that offsets the benefits of sustained work and goes beyond just a way to resist pressure from the assigners of the tasks.

In my search for clarification, it was helpful for me to talk to the American impressionist painter John C. Terelak, who juggles tasks all the time and for a clear reason: It makes him a better artist.

He structures his working life so that five to 20 paintings are in progress at a time, hanging on his Florida studio wall. That way, each one’s individual problems are easier to see and solve. “In the past, when I put all my energies into one painting at a time, there were times I could not solve the problems in the paintings,” he told me. “I’d get depressed. I’d get down on myself.”

Now, by comparing them, he can see why some don’t measure up: The sky in this painting is too dark, or this human figure is out of place, or this color scheme is out of harmony.

The paintings also compete for his attention, giving him choices about what to work on each day. “That way my paintings don’t become rote,” he says. “They become individual things that change daily. It keeps me from being a formula painter.”

That’s at least part of the perspective I was looking for: When you juggle, your tasks interact with each other, and that can be a good thing. As they compete for your attention, their specific problems come into sharp relief, and new solutions present themselves. You get out of a rut, you stay fresh. You borrow ideas from one task and apply them to others.

There’s another advantage to juggling that was suggested by a recent study from Haiyang Yang of Insead Singapore and colleagues: Getting your head out of one task and into another allows you to temporarily shut down your conscious thinking about the first one so that your unconscious mind can go to work on it. Under the right circumstances, unconscious thought can be more effective than conscious thought in producing innovative ideas. In Yang’s study, a three-minute time-out for a highly distracting word task helped people come up with more-novel ideas for designing a children’s toy.

That’s happened to me. After I leave a tough mental task, think about something else, and then return, the task somehow gets easier. I think it’s mainly because of this phenomenon that I first got into my task-jumping habit, but I can see that I also benefit from the Terelak effect, or effects (plural), namely that juggling enables productive comparison and a choice of tasks to work on.

When tasks accumulate at a frantic pace, the multitasking really picks up, requiring a concentration level that can border on the manic. I notice this after a holiday break — it takes me about a week to get back into that revved-up frame of mind. But soon I’m back in gear again, skipping easily from task to task, feeling a lot like Neo when he’s literally dodging bullets.

Even though this manic rhythm may reduce my likelihood of finishing a given task in a given time period, it feels highly effective — there’s even a certain pleasure in it. Under these circumstances, task juggling seems to become its own form of flow state, every bit as engrossing and productive as the most intense monotasking.


Andrew O’Connell, an editor with the Harvard Business Review Group, is the author of Stats and Curiosities from Harvard Business Review.



Your Turn To Talk

Your email address will not be published.