Dear Leaders,

Sometime in the 1920s, the psychologist Kurt Lewin was sitting in a Berlin café with his students when he noticed something odd about their waiter. The man could recall every unpaid order at every table without writing anything down. Once a table settled its bill, the order vanished from his head. Ask him a few minutes later what those people had eaten and he had no idea.

One of Lewin's students, a young woman named Bluma Zeigarnik, took the observation back to the lab and confirmed it. The brain keeps unfinished business in active storage. It keeps it warm, keeps checking on it, and keeps paying rent on it. Finished business gets released. The tab closes, and the mind lets go.

Hold on to that waiter. We'll come back to him.

Most of the people I advise have spent decades in roles where intensity is the baseline. Sixty- to eighty-hour weeks are the norm, not a crisis. They compete for a living, they win more than they lose, and most of them, if we're being honest, are a little turned on by it.

Over the past year, and faster over the past few months, roughly nine in ten of them keep telling me they're exhausted. Some say things that used to satisfy them, at work and outside it, now just register as items completed. Others have started watching themselves for signs of cognitive decline. Is this the early edge of something serious, or have they simply lost a step? Either way, the worry becomes a weight of its own. Now they're tired and anxious about being tired.

Something this persistent can have a medical or psychological cause, and anyone feeling it should see the right professional.

And yes, I know what some of you are thinking: Hamza, if this is happening to most of your clients, maybe you're the cause. Hey, maybe. My sisters would probably agree with you.

But before we start pointing fingers, let's look at what's actually changed. What's more, our default response to those changes may be making things worse. What follows is my attempt to make sense of it all.

We tend to simplify executive exhaustion as a volume problem. Too many hours, too much responsibility, too much stress. But volume isn't new. What changed is what fills the rest of the day.

Over the last twenty years or so, since most of us started carrying a smartphone, we put enormous money and engineering into removing friction from daily life. We used to stand on the corner and wave for a cab. Now we tap a phone and the car is waiting before we're outside.

Each convenience was a gift on its own terms. But every bit of friction we removed was also a pause we removed. The wait for the cab, the walk to the next meeting, the hours on a plane when nobody could reach us. None of it was designed as rest, and all of it worked as rest. We took out the gaps and kept the load.

At the same time, we dramatically increased the amount coming in. Work used to be the main thing we had to manage. Now work sits inside a much larger stream of information competing for the same attention.

A twelve-hour workday is one kind of load. A twelve-hour workday broken up by two hundred emails, frequent texts, a dozen Slack threads, headlines, market moves, LinkedIn, family logistics and whatever else happened to reach us that day is another. We used to manage workload. Now we have to manage total cognitive load.

We've built a way of working in which the brain is asked to process something new every few minutes, often every few seconds, and is then denied the uninterrupted stretch it needs to finish processing what came before. The result is an executive who is rarely fully working and almost never fully resting.

Back to the waiter. Every open item is a table that hasn't paid.

The email we read but didn't answer. The text we meant to return. The thread we'll get to after this call. The deal update we skimmed in the elevator. The article we opened and never finished. The question we meant to ask someone. The thing we need to remember when we get home.

Zeigarnik's waiter could handle a busy lunch because lunch ended. Ours doesn't. The tables keep filling, and the restaurant never closes.

Gloria Mark at UC Irvine has spent about twenty years measuring how long people stay on one screen before switching to another. Today the average is forty-seven seconds, down from two and a half minutes in 2004. And once people switch away from a piece of work, it's typically about twenty-five minutes before they return to it, usually after detouring through other tasks along the way.

Here's the part that might sting a little: in her research, we interrupt ourselves more often than other people interrupt us. The switching leads to what’s called attention residue. When we leave one task for another, part of our minds stays behind. We're in a meeting, but a slice of us is still in the email we just read. Do that sixty times a day and we are never fully anywhere.

We're a crowd of partial selves, each doing a partial job.

It gets stranger. We don't even need to be interrupted. The mere expectation of an interruption — a text, an email, whatever — carries a cost of its own. Here too, research is clear that simply having a phone on the desk, face down and silent, is associated with less available working memory than leaving it in another room.

Part of our brain is busy not checking the phone. We are paying rent on a table nobody is sitting at.

Now compare that with an evening spent on a dense novel. Let's say Russian literature. Six hundred pages of Russians with three names each look like harder work than scrolling.

In reality, that's not the case. A novel gives the brain one story and one place to be, long enough for the part of it that's always scanning to finally stand down. Scrolling feels like rest but works like labor. The novel feels like labor but works like rest. No wonder we're told to read a book when we can't sleep.

The amount of information isn't the only problem. The kind is.

Much of what reaches us was built to get through. Headlines written to alarm, feeds ranked for outrage, notifications timed for maximum pull. Every few seconds our brain has to reorient to a new and unrelated context, and many of those contexts come loaded with an emotion.

A small jolt of fear. A flash of anger. A twinge of envy. A wave of outrage over something happening four thousand miles away that we can do absolutely nothing about.

Some of it does more than pull at our attention. It unsettles our sense of who we are.

For most of history, the people we measured ourselves against were the people we actually knew: the neighbor, the classmate, the rival across town. Now the comparison set is everyone.

The peer who just closed a bigger fund, the former colleague on a beach in Mykonos, the founder half our age on a magazine cover. And we carry all of them in our pockets and check in on them all day long.

A few decades ago, information had natural barriers. The newspaper came once a day. So did the mail. The phone was attached to a wall. None of these were designed as filters, but they worked as filters. We removed every one of them and never replaced them with rules.

Think about how protected our calendars are. Most of us have someone whose job is to decide who gets thirty minutes of our time. Almost none of us have anyone deciding what gets thirty seconds of our attention.

When everything gets in, the thing we actually needed often loses.

Air travel used to come with a hidden mercy. Once the door closed, we were unreachable. Six hours over the Atlantic was forced quiet, whether we wanted it or not. Then planes got Wi-Fi, and the last sanctuary closed.

Now we board in New York, answer email over Greenland, land in London, take a call on New York time and another on Hong Kong time, and try to get a good night's sleep.

The body adjusts to a new time zone slowly, roughly a day for every zone crossed. Plenty of executives now cross them often enough that the body never fully lands anywhere.

Sleep is where the brain consolidates what it learned and clears out its metabolic waste. Shorten it and break it up, month after month, and some of what feels like cognitive decline is simply a brain that hasn't been allowed to take out the trash.

The office lost its gaps too. Video calls removed the walk between meetings. The five minutes in the hallway. The elevator ride where the last conversation got filed away before the next one began. Back-to-back used to come with forced gaps. Now one meeting ends at 10:59 and the next begins at 11:00.

Those gaps gave the brain time to finish one thing before starting another. We removed the processing time and kept adding things to process.

Then there's AI, which is about to speed all of this up again.

I suspect it's no coincidence that the exhaustion I'm hearing about accelerated over the past year, as these tools moved into everyday use.

Think about the last time something was bothering us about a colleague, a client or our spouse.

Not long ago we had two options: talk to the person, or talk it over with a friend or a therapist and then, maybe, talk to the person. Either way, there was a natural limit. The friend got bored, and the therapist's hour ran out.

Now there's a third: we can open a chat and work through it with a machine that never tires of the subject. Then we can do it again that evening, from a slightly different angle. And again the next morning.

It's patient, articulate, always available, and very good at producing one more consideration. One hard conversation becomes a dozen conversations about the conversation, and the real one still hasn't happened.

Meanwhile, the information available on any subject, true and otherwise, has gone from vast to effectively endless. There's a hopeful view that AI will hand us time back. Maybe. But it's likely to fix the production bottleneck well before it fixes the attention bottleneck.

When a tool gives us twenty percent more capacity, do we put any of it toward recovery, or does all of it go to more output? So far, it's been all output.

Email was going to save us time too. We all know how that went.

Not long ago I was walking with a friend, an executive who runs a fast-moving, high-energy organization spread across several time zones.

She told me she feels constantly on. She feels bad that she can't get back to people in a timely way, and sometimes not at all, because things slip.

Then, almost as an aside, she said she used to love playing the piano but hadn't played in a very long time, even though a piano sits in her living room.

I asked what would happen if she played today. Just for five minutes.

She said she couldn't. Then she gave me several reasons why she wouldn't have five minutes to herself for the rest of the day. Every one of her reasons was legitimate.

That is the real cost. It isn't just that we're busy. The things we actually want to do start losing to the things coming at us.

That happens at work too. The thoughtful memo loses to the inbox. The difficult decision gets pushed while three easier ones get made. The hour we meant to spend thinking gets broken into twelve smaller pieces.

Nothing is necessarily going wrong. There is simply always something else coming in. Eventually the things that require uninterrupted attention start losing.

The short version is that eventually something makes the decision for us.

People at senior levels are very good at borrowing against the future. It's partly how they got here. Health, attention and relationships extend credit for a long time, and then they call the loan: a cardiac event, a marriage that became only logistics long before either person admitted it, a significant decision made by a brain running on fumes.

Judgment is the asset we're paid for. It's also the first thing to degrade under these conditions and the last thing we'll notice degrading, because the instrument doing the noticing is impaired. When the bill finally comes due, we don't get to choose the currency.

Which brings us to what to do about it. The answer, as usual, is much simpler than the problem.

The common denominator we're aiming for is uninterrupted time: time with ourselves and time with our loved ones.

Protecting it means undoing, on purpose, some of what the last fifteen years did by default.

Each problem above points to its own answer. If we interrupt ourselves more than anyone else does, the phone can be kept in another room for that hour instead of face down on the table.

If someone guards our calendar but nobody guards our attention, that has to change: decide who can interrupt us during the day, who can reach us after hours, and how. Everything else can wait.

If the feeds are built to provoke us and make us compare, don't be accessible to them all day.

If the hallway and walk between meetings have disappeared, we end meetings at twenty-five or fifty minutes and take that short window to ourselves.

If the flight was the last quiet place left, leave the Wi-Fi off on some of them.

And if something about a person has us going round and round with a machine, stop after one round and have the conversation. It's the only thing that actually closes that tab.

None of this is clever. We removed the friction one convenience at a time, and we'll have to put it back the same way.

How the time we gain is allocated depends on each person's situation. If you have a newborn at home, an uninterrupted hour with your child probably matters more than getting back to the piano. If you've spent ten years saying you want to write, the answer may be fifteen minutes alone with your journal. Someone else may need dinner with their spouse, a long walk, or twenty minutes by themselves.

There are a few basics I'd treat as non-negotiable: exercise regularly, spend some time in quiet, and write things down. They each give the brain something our current environment rarely does on its own: sustained attention, less incoming information, and somewhere for unfinished thoughts to go.

Zeigarnik's waiter wasn't a memory genius. He was a man whose shift ended. The tables paid, the tabs closed, and his mind let go. The executives I work with don't have a stamina problem; most have spent decades proving the opposite. It's a load problem: too much gets in, too little gets processed, and almost nothing is allowed to end.

The world isn't going to become less available. We have to become less available to it.

Onward,

Hamza