How does multitasking impact productivity and brain health?

You know the day I am talking about. Your phone lights up before breakfast. You skim a partner deck while replying to a Telegram from your lead engineer, half listen to a podcast about scaling culture, and start drafting investor notes in the Notes app. You tell yourself this is the price of being a founder. It feels busy. It feels important. It also feels like momentum. By evening, the work is somehow both exhausting and unsatisfying. You touched everything, yet nothing feels truly done.

I used to call this pace adrenaline. Then I learned to call it what it is. Attention debt dressed up as productivity.

Multitasking sounds efficient because the word promises parallel progress. In a lab, true parallel processing requires separate systems that can run without interfering with each other. In a startup, those systems live inside one brain, yours. What looks like simultaneity is usually rapid switching. Every switch carries a small cost. One more context to reload, one more set of rules to re-activate, one more quiet thought that gets interrupted before it forms. The tax is tiny in seconds and heavy in totals. It shows up as drift, shallow decisions, and the kind of mistakes that only appear when a user finds them first.

The odd thing is that multitasking often begins from a good place. Founders are generalists by necessity. You fill gaps. You keep the fire going. You try to be everywhere the company feels fragile. The problem is not capability. The problem is friction. Switching focus makes simple tasks feel heavy and complex tasks feel impossible. You end the day tired in the body and wired in the mind, which is the worst combination for clear leadership.

Here is the pattern I see when teams normalize multitasking. The first loss is comprehension. You read more words and remember fewer of them. Conversations feel shorter and outcomes feel fuzzier. The second loss is accuracy. Minor errors slip into proposals, commits, or invoices. Each one is fixable, but together they create a perception problem with customers and investors. The third loss is speed. You think you are going faster because you touched five workstreams in one hour. In truth you are moving slower because none of those workstreams received the uninterrupted attention required to complete and ship.

The brain explains this better than any productivity guru. Executive functions handle goal selection and rule activation. When you switch, you ask that system to downshift one set of rules and load another. That is fine if you are folding laundry while chatting with a friend. It is costly when you are reviewing a security design while monitoring a sales call. Small, repeated costs accumulate. They also drain the fuel you rely on for the work that only you can do, the work of setting direction and protecting standards.

There is a second trap. Multitasking raises distractibility. The more often you let yourself switch without consequence, the more your mind treats every ping as equal. You become easier to pull off course even when you promise yourself you will focus. Your team reads your behavior as permission. Meetings grow noisy. Slack threads become parallel meetings inside meetings. Delivery slows. Morale follows.

If this sounds harsh, let me tell you a story that still embarrasses me. During a hiring push, I kept a dashboard open with live funnel metrics while interviewing product managers. I felt responsible for both the talent bar and the weekly targets, so I tried to hold both in my head. In one interview I nodded at a thoughtful answer, then asked a follow-up that had already been answered two minutes earlier. The candidate smiled politely. I saw it land. We did not hire that person. They did not accept our offer. Both can be true.

The turnaround did not begin with a new tool. It began with a new rule. One brain, one task, full respect. I designed my day like an operating system rather than a sprint board. I did it because the company needed an adult in the room and, on too many days, that adult was not me.

Here is how I rebuilt the rhythm. I use the word rhythm deliberately, because routines feel like cages to founders. Rhythm feels like music.

First, I separated work by interruptability, not by department. Anything that breaks when interrupted, such as architecture review, product narrative, pricing logic, receives a protected block with hard edges. Anything that survives interruption, such as approvals, vendor replies, scheduling, lives in a separate corridor of the day. The team learned those edges quickly because I modelled them consistently. I still answer fast. I just do not answer always.

Second, I created a focus budget. A budget is not a wish. It is a limit. I chose two blocks a day for deep work, usually ninety minutes in the morning and sixty minutes late afternoon. The calendar marks them publicly. The phone lives in another room. If someone needs me, they ask through a single escalation channel with a clear definition of urgent. Urgent means user harm, security risk, cash risk. Everything else waits ninety minutes. The company did not break. Our work got cleaner.

Third, I rewired the handoffs. Multitasking thrives in low-clarity handoffs because everyone is half owning everything. We switched to a single owner per outcome, visible in the spec and reflected in the standup narrative. Contributors still contribute, yet the owner decides, sequences, and closes. Ownership reduces thread sprawl because questions have a home. It also reduces the emotional load on the founder, which is the quiet win nobody markets.

Fourth, I adjusted the dashboard. Founders think dashboards create calm. Sometimes they create compulsion. I removed real-time vanity metrics from my field of view during deep work. I still review them daily, just not while writing a product brief. This sounds trivial until you experience the difference between a mind that glances at a number every five minutes and a mind that sits with an idea long enough to find its shape.

Fifth, I taught the team to protect each other’s attention. We agreed on quiet hours for core roles. Sales protects product in the morning. Product protects sales in the late afternoon. People still talk. The talk just matches the energy of the work. Meetings shortened because people arrived with context instead of hunting for it live. We also made meetings smaller. Fewer listeners, more doers. The meeting notes improved because the note taker was not also crafting a pitch deck on a second screen.

You might worry this will slow responsiveness. The opposite happened. Short feedback cycles on the right work outperformed instant replies on the wrong work. Customers felt the difference in the quality of what we shipped. Investors felt the difference in the quality of what we said. Most importantly, the team felt the difference in the quality of their own days. People stopped apologizing for turning notifications off. They started finishing things. That is culture. Not the poster, the feeling that your attention matters here.

Let me be clear about one more thing. Restored focus is not about perfection. Life in Southeast Asia includes late calls with West Coast investors, morning standups with engineers in Jakarta, and the occasional crisis that ignores your calendar. Focus is about defaults. When your default is single-threaded, the exceptions stop becoming the identity of the company.

If you are trying to change this inside your team, begin with yourself. Choose one week to treat your attention like capital. Name where you will spend it. Name where you will not. Tell your team the plan in plain language. Ask them to hold you to it. When you slip, reset without drama. Do not make it a hero story. Make it hygiene.

There is one more piece that founders underestimate. Single-tasking reveals quality gaps that multitasking can hide. When you give a product spec ninety focused minutes, you notice the non-decision that looked harmless yesterday. When you give a customer interview your full presence, you hear the emotion under the words. When you give your hiring process your full attention, you spot the mismatch in values before it becomes a performance issue that costs three months of runway. Focus is not only a speed play. It is a risk control.

What about creativity, you might ask. Some of your best ideas arrive while you cook, walk, or shower. That is not multitasking. That is letting your brain recover from directed effort. Downtime is not diluting focus. It is fertilizing it. The distinction matters. When you protect deep work, you also protect the space that feeds it.

Here is how you will know the shift is working. Your calendar looks less heroic. Your inbox looks slightly slower in the first two hours of the day and much cleaner by evening. Your team starts booking you for decisions rather than updates. Your roadmap stops changing every week because ideas finally have time to be tested before they are promoted. You end days tired in the body and calm in the mind. That is the combination that builds companies that last.

If you need a first experiment, try the twenty minute rule for one morning. Choose the one task that scares you because it matters. Commit to twenty minutes of undivided attention, then decide whether to continue or switch. Most of the time, twenty minutes will carry you into ninety without force. If you do switch, switch with intention rather than impulse. Name the next task. Close the loop. Move.

I mentor female founders who are building in Kuala Lumpur, Singapore, and Riyadh. The contexts differ. The pressure to be always on feels similar. My advice is consistent. You do not have a time problem. You have an attention problem. Solve that and your time improves automatically.

Multitasking sells a fantasy that founders feel vulnerable to. It says you can be a great CEO, product lead, sales director, community builder, and parent in the same hour if your calendar is colorful enough. Focus tells a different story. It asks you to be one thing at a time, with your whole mind, so the company receives your best in a sequence it can absorb. That is not slower. That is sustainable speed.

If you take nothing else from this, take the permission to work like a human with one brain. Your company does not need your constant presence. It needs your clear judgment and your finished work. Give it those two things and watch how the rest follows.