Multitasking hurts productivity

By Jim Grey (about)

“You multitask like a madman,” my boss said to me.

She meant it as a compliment, but it brought me down. I was exhausted, teetering on the edge of burnout precisely because I had been multitasking an enormous workload.

Not a skill to be praised

I managed 15 people across four teams: testers that delivered monthly bug-fix releases, test automation developers, performance testers, and technical writers. My teams were solid and I had great leads in place, which freed me to work with a security-testing vendor to start doing regular penetration tests of our product, and with a translation company to translate our product user interface into five languages each release. I had a lot going on, but I was handling it.

But then the company decided to lean hard into more international markets. The executive team asked me to gather quotes to translate our product UI into even more languages, and also to translate our giant online help system, which we had only ever offered in English. The costs were an order of magnitude more than the executive team imagined, and so I was called into endless meetings and hallway discussions to provide more data as the executives squabbled with each other over strategy. This all sucked down more than a third of my time – but I could never focus on this work for more than ten or twenty minutes because I was still managing four teams with leads who had questions and needed me to remove roadblocks.

My performance began to suffer. While I had my eye on one ball, another would drop. I started making silly mistakes. It all wore me down to a nub. To keep sane, I ended up not asking, but telling my boss to take things off my plate so I could survive. I really wanted the translation stuff to go, as I didn’t enjoy it very much. But instead she gave the technical writing and bug fix teams to other managers.

I really mean task switching, not multitasking

Everybody calls what I was doing multitasking, but it really wasn’t. Real multitasking is when we do more than one thing at a time, such as driving and talking, or walking and chewing gum. But when two things come along that require focused attention, most of us can’t do them simultaneously. We work on one task, and then we work on the next. That’s really called task switching, and it happens every time we stop testing a feature release to test an emergency hotfix, or even get interrupted to answer a question. I’ve just called it multitasking here so far so that Google’s sweet, sweet searches can find this post.

Task switching makes tasks take longer overall. It also hinders learning – all that switching from one task to another keeps things from sticking in our brains. It really is better to work on, and finish, one thing at a time. We are so much more productive that way.

The hidden costs of task switching

Say you’re working on task A when task B arrives. If you want to avoid task switching, you finish task A and then work on task B.

But say task B is hot, and your boss needs you to work on it right now. Task B goes out sooner, at the cost of delaying task A.

But there’s a hidden cost: unless a task is automatic or menial, it takes time to get oriented to it, even when you’re returning to it after only a brief interruption. You must at least try to remember where you left off. That orientation time delays overall completion.

This cost mounts the more you switch tasks. If you switch repeatedly among tasks A, B, and C, not only do all tasks finish later, but tasks A and B finish much later.

Task switching hinders learning

One of my first jobs was working the counter at a Dairy Queen. It took me a couple weeks to learn the technique for creating their soft serve’s signature shape, but then I could do it without even thinking about it. It had become a habit.

Making software isn’t the same as making ice-cream cones. Being effective and productive is much more about deepening skills and knowledge than about building habits.

Single-tasking helps deepen skills and knowledge because it stimulates the hippocampus, which is part of the brain that puts information in long-term memory. Task switching hurts this because it stimulates the basal ganglia, which is the part of the brain that is good at building habits.

In software development, you simply get better at what you do faster when you single task.

What to do then?

It’s impossible to entirely eliminate task switching – emergencies will arise, questions will need to be answered. And I do believe in the power of collaboration to deliver better software. But it’s a good investment to minimize task switching as much as you can.

If you’re in management, make singletasking a value. Demonstrate it by removing obstacles so people can focus on one thing for long periods:

• Can you have “do not disturb” periods or let people work from home when they need to complete a critical task?
• Can you give people private offices?
• Can you schedule meetings that involve your team members so they don’t interrupt work as much, such as first thing in the morning, just before lunch, or at the end of the day?
• Can you organize your teams so that you have people dedicated to handling customer emergencies (in a prioritized way, so they can focus on one at a time) and people dedicated to building new product?

If you’re not in management, you can still do a lot to clear your decks so you can concentrate:

• Adjust your work schedule so that you arrive earlier or stay later than most others. (My normal work hours have been 7:30 to 4:30 for more than 20 years. The first 60-90 minutes of the day are my most productive because few others are in the office.)
• Stop responding to e-mail as it arrives; instead, set aside specific times when you read and respond to it.
• Work out a do-not-disturb convention with your team. In one group I worked with, we placed a little blue flag on our desk when we needed to go heads down.
• Ask if you can work from home when you really need to concentrate.
• At least put on your headphones, which many people interpret as a sign that you don’t want to be disturbed.

And of course, when your boss pulls you in too many directions, be sure to ask him or her to help you prioritize your work so you can focus on one thing at a time, or to assign work across your team in ways that balances the load. Multitasking alone doesn’t usually lead to burnout, but it absolutely brings you there faster when you have too much on your plate.