The Actual Reason Everyone Is Exhausted at Work and the Problem with Juggling Water

by | Leadership, Productivity

I’d like you to imagine something.

As your manager, I’ve just given you a pitcher of water and tasked you with taking it from one side of the room to another. Accomplishing the goal is important, but quality also matters, so you can’t spill a drop. Oh, and of course, we’re on a deadline, so you need to get it there as fast as possible.
It sounds a little challenging but not too hard, right? You imagine you’ll complete the task pretty well.

And because you’ve done well, I’m now going to ask you to take the pitcher, pour the water into four cups, each one full to the brim, and walk the four full cups across the room, using only your hands. As before, there’s a tight deadline so you’ll have to be fast but quality is just as important as it was before so you can’t spill anything. You’ll have to figure out how to check the speed and quality boxes while juggling sloshing cups.

It’s fundamentally the same thing you’ve already done — you’re moving an equivalent amount of water across the same distance — so it shouldn’t be a problem.

But this task doesn’t feel the same. Because it’s not the same at all.

What seems like an equivalent job on paper suddenly becomes more difficult in real life.

You might manage to juggle those cups across the room, but it’s going to be harder. You will move more slowly and there’s a greater risk you’ll spill at least a few drops of water.

Now, imagine that you successfully transported those cups. I’m so pleased — and so confident in your abilities — that I want you to take on a new creative project. I also know now what your capacity is and don’t want to overwhelm you so I’m going to give you the same amount of water and the same distance to carry it. Only this time, you have to carry it in four cups and one strangely shaped vase.

Of course, this job is going to be a lot harder, no matter how good of a water carrier you are. The speed and quality of your performance will decrease and internally you’ll feel stressed and disappointed in yourself for failing to carry water like you used to.

As your manager, I can’t figure it out. Why is your performance dropping? After all, I was so careful not to change the amount of water.

The peculiar math of capacity management.

You can see the problem here: the task is the same, sort of, but the work is completely different and, more significantly, your capacity to complete the task has changed dramatically. There is no good way to juggle water in multiple containers across a room with just your hands.

In organizations, this trick of dividing time and energy is called capacity management.

And it contains a fundamental flaw.

You might be tasked with one project that’s meant to take up 20% of your capacity, one that’s meant to take up 60%, another that’s supposed to take up 5%, and a final one that should take up 15%.

On paper, the math checks out. In reality, however, you feel overworked, you’re scrambling to keep up, and this turns to internalized doubt that you’re doing something wrong or that you’re not the high-performer you believed yourself to be.

It’s easy to see how this might play out with physical tasks, like the water experiment above where we struggle when the number of cups exceeds the number of hands we have, but it’s harder to grasp when we shift to the realm of cognitive work. The tangible capacity limit often seems to disappear.

It feels like we should be able to multitask, so we try to divide our time into fractions that we use to accomplish different types of work and then wonder why we — and the people in our teams — aren’t performing to the level we expected.

Here’s the flaw in that thinking: our brains just don’t work that way.

The reality is that humans can’t be divided into percentages and parts and still work the same way.

After extensive studies on thousands of people’s brain activity as they completed various cognitive tasks, researchers at the Vanderbilt Center for Integrative and Cognitive Neuroscience concluded: “Despite the impressive complexity and processing power of the human brain, it exhibits severe capacity limits in information processing. Nowhere is this better illustrated than when we attempt to perform two tasks at once.”*

Now, I know what you’re thinking: “But I do that all the time.”

It may be true that you (like so many of us) regularly catch up on emails during meetings or check tomorrow’s to-do list mid-way through writing a report. However, when you do so, your focus is fractured, not equally divided.

Those fractured moments come at a cost, from wasted time and employee stress to lower quality of work and ineffective collaboration. These losses multiply as one person turns into a team and as teams turn into an entire organization. And when you have a large group of people trying to juggle water in a bunch of cups and vases, the spilling soon adds up.

Suddenly there’s a flood on your hands! But you can reverse — or even avoid — the flood by accepting the reality of how our brains function.

Human brains and their executive functions.

Executive functioning is kind of what it sounds like: the executive management of our brains. These functions make it possible for us to play around with new ideas, change our mindsets, explore creative ways to solve problems, think before acting, manage communication, respond to unanticipated challenges, and focus.

The executive functioning capacity of our brains evolved to collaborate, solve seemingly intractable problems, and innovate in powerful ways. But it does this by enabling only one executive functioning at a time — a principle often referred to as the bottleneck phenomenon.

This bottleneck phenomenon dictates that if your brain is presented with multiple cognitive tasks to complete, it can’t tackle them all simultaneously and so it will form a queue for the tasks. That sounds wonderfully efficient, but there’s a catch: managing that queue comes with a cognitive load, and the longer the queue the greater that cognitive load will be.

What that means in practice is that the more tasks you have waiting, the more slowly you’ll work and the length of time you need to complete each task will increase every time something new is added to your list.

Even if you only have two tasks waiting, you’ll spend about 40% of your time context switching — reorienting the brain, identifying and switching to new goals (also known as goal shifting) and assessing the different rules associated with different tasks and different situations (also known as rule activating) — and leaving only 60% brain power to actually complete the tasks.

This context switching, encompassing as it does the executive functions of goal switching and rule activation, is hugely demanding. And since most of us are trying to make progress on multiple important tasks in any given day, week, or month, the cognitive load of context switching that tallies up to a huge tax paid in time and energy.

This is why you and the people you work with probably feel constantly exhausted, teetering on the edge of burnout.

You aren’t alone in this struggle — it’s a problem facing nearly every organization.

You also aren’t a bad leader if you find this truth hard to swallow. After all, it would be far more convenient to plan and accomplish goals if humans could multitask without the negative impacts on quality, outcomes, and human wellbeing. And despite the conclusive science on the drawbacks of multitasking, we’re fighting against some pretty powerful illusions that make us want to cling to the status quo or believe that the costs associated with multitasking are unavoidable.

Unfortunately, that’s not the reality we’re working with and if we learn how to work with the evolution of the human brain, rather than fighting against it, we’ll go a long way towards creating teams that feel more energized, more resilient, and happier in their work.

Here’s how to start…

Take action now.

For now, simply start paying attention to the number of cups, vases, and other vessels you’re trying to juggle each day.

If you’re not sure, check your calendar: on your last workday, how many meetings did you have? On how many topics?

How many different initiatives, goals, projects are you responsible for in a given week?

Each of those initiatives, goals, and projects is like a different cup, full to the brim — and you likely have a lot of them.

Now, you probably wouldn’t want to be responsible for that number of physical cups, yet you’re forcing the same number of cups into your head.

Recognizing the strain your brain — or your team — is under is often the “aha” moment you need to realize that there’s a legitimate reason for your end-of-day exhaustion and that the struggle to cope does not mean that you’re not a high performer. And it’s often the exact impetus you need to reconsider how you manage and distribute your “water” as you move it from one side of the room to another.

*Paul E. Dux et al., “Isolation of a Central Bottleneck of Information Processing with Time-Resolved fMRI,” Neuron 52, no. 6 (December 2006),

If you found this helpful, you’ll love my new book, Real Flow: Break the Burnout Cycle and Unlock High Performance in the New World of Work.

Order it now and discover how to design a high-performing, agile organization, improve employee retention, and stop burnout in its tracks.


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