Barack Obama owned 30 identical suits. This wasn’t a fashion statement—it was a strategic decision to preserve his most valuable resource: cognitive capacity. Former US Secret Service Agent Evy Poumpouras observed this pattern across multiple presidencies during her time protecting the nation’s leaders. What she discovered revolutionized how she thinks about decision-making, productivity, and mental performance.
In her conversation on The Diary of a CEO podcast with host Steven Bartlett, Poumpouras shared what she calls “the bathtub theory”—a simple but powerful framework for understanding cognitive load that explains why high performers operate differently than everyone else.
Your Brain Is Like a Bathtub
“Your brain is like a bathtub,” Poumpouras explained. “Your cognitive load is like a bathtub. The bathtub can only hold so much water. If you keep putting water in the bathtub, it’s going to overflow. That’s your cognitive load.”
This metaphor captures a fundamental truth about human mental capacity that most people ignore: your brain has finite processing power. When you exceed that capacity, everything suffers.
“If I have my cognitive load, my bathtub, and I keep putting water, water, water, it’s going to overflow,” she continued. “Your cognitive load is overflowing. It’s maxed. You’re inefficient. You’re sloppy. You’re not getting things done right. If you are, you’re just barely getting there. You’re everywhere. You’re stressed out. You’re frazzled because you’re maxed out.”
The implications are profound. Most people operate in a permanent state of cognitive overflow, wondering why they feel overwhelmed, make poor decisions, and struggle to focus.
What Poumpouras Learned from Watching Presidents
During her years protecting multiple presidents—including Barack Obama, George W. Bush, and Bill Clinton—Poumpouras identified consistent patterns in how these high-performing leaders managed their mental resources.
The Power of Subtraction, Not Addition
“You know what good leaders do?” Poumpouras asked. “They take out of that bathtub. They take out. What can I do less of so I can be exceptional at the other things I do?”
This is the fundamental mistake most people make: they think success requires adding more. More tasks, more responsibilities, more commitments, more hustle. Leaders understand that excellence requires ruthless subtraction.
President Obama’s 30 identical suits exemplified this principle. By eliminating one daily decision—what to wear—he preserved mental energy for the thousands of consequential decisions he faced as president.
“He didn’t want to sit and figure out what he’s going to wear,” Poumpouras explained. “It’s a decision he didn’t have to make. That keeps his bathtub light.”
Delegation as Cognitive Protection
Another pattern Poumpouras observed: presidents were very good at delegating. They didn’t need to know everything because confident people are comfortable with not having all the information.
“Your bathtub can only hold so much,” she noted. “So everything I do, and I will tell you, I learned this from watching presidents: I keep my load light. My bathtub only holds the water it needs to hold in.”
This approach contradicts common assumptions about leadership and success. We imagine high achievers cramming more into their schedules, learning every detail, and controlling every aspect of their domains. In reality, the most effective leaders protect their cognitive capacity by strategically limiting what enters their bathtub.
The Hidden Cost of a Full Bathtub
When your cognitive load overflows, the consequences extend far beyond feeling stressed or overwhelmed. Poumpouras identified several critical impacts:
1. Decision Fatigue Leads to Bad Decisions
“It protects you from overextending yourself, stressing yourself, and it also keeps you from making bad decisions,” she explained. “There’s something called decision fatigue where the more stuff I add, we think the busier I am, the better I am.”
Research confirms this observation. Studies show that the quality of decisions deteriorates as mental fatigue increases. Judges are more likely to grant parole at the beginning of the day than at the end. Doctors make more diagnostic errors during long shifts. Executives make riskier choices when cognitively depleted.
Just because you’re busy doesn’t mean you’re being productive. Those two things are not synonymous, despite what hustle culture suggests.
2. Emotional Regulation Breaks Down
Your emotional governor—the internal mechanism that manages reactions and keeps you professionally composed—requires cognitive resources to function. When your bathtub overflows, your governor goes “out to lunch,” as Poumpouras put it.
This explains why you might snap at a colleague over something minor at the end of a draining day, even though you handled bigger frustrations calmly in the morning. Your capacity for self-regulation is finite and depletes throughout the day.
3. Performance Becomes Sloppy
“You’re inefficient. You’re sloppy. You’re not getting things done right,” Poumpouras said of people operating with cognitive overload. “If you are, you’re just barely getting there.”
Excellence requires mental space. When you’re maxed out, you can only manage maintenance-level work. You lose the capacity for strategic thinking, creative problem-solving, and high-quality execution.
The Overanalyzing Trap
One of the most insidious ways people overflow their bathtubs is through excessive analysis and rumination. Poumpouras addressed this directly when discussing why people spend so much time trying to understand their past.
“Why does it matter?” she asked. “I don’t understand why we have to psychoanalyze everything we do. I feel we waste so much time in trying to figure out I’m like this today because of this, this and this.”
The cognitive resources spent on constant self-analysis and rumination fill your bathtub with water that serves no productive purpose. Understanding why you are the way you are doesn’t change what you need to do today.
“If you are, you’re just barely getting there. You’re everywhere. You’re stressed out. You’re frazzled because you’re maxed out,” she observed about people trapped in analysis paralysis.
How to Apply the Bathtub Theory to Your Life
The bathtub framework offers practical strategies for improving decision quality, reducing stress, and enhancing performance:
1. Conduct a Bathtub Audit
Identify everything currently in your cognitive bathtub:
- Recurring decisions you make daily
- Tasks and responsibilities you’ve accumulated
- Relationships requiring emotional energy
- Projects and commitments
- Information you’re trying to track
- Problems you’re attempting to solve
Be honest about what’s actually in there. Most people dramatically underestimate their cognitive load.
2. Practice Ruthless Subtraction
Using your audit, ask: “What can I remove from my bathtub?”
Start with decisions:
- Standardize your wardrobe for work (like Obama)
- Plan meals in advance or create a rotation
- Automate bill payments and routine tasks
- Create default responses for common requests
- Establish standing meetings instead of scheduling repeatedly
Then remove tasks:
- Delegate what others can do 70% as well as you
- Eliminate activities that don’t align with core goals
- Say no to new commitments that don’t subtract something else
- Automate or batch repetitive work
Finally, manage information:
- Unsubscribe from newsletters you don’t read
- Limit news consumption to specific times
- Turn off non-essential notifications
- Create systems for information you need to retain
3. Protect Your Morning Bathtub
Your cognitive capacity is highest in the morning. Guard this time for your most important decisions and creative work.
Poumpouras noted that presidents would study and prepare during early morning hours. They protected this fresh cognitive state for work requiring their best thinking.
Stop checking email, scrolling social media, or attending to minor tasks first thing in the morning. You’re pouring water into your bathtub before tackling what matters most.
4. Build Strategic Ignorance
“Confident people are okay with not knowing all the information,” Poumpouras observed about presidents. They surrounded themselves with experts and trusted others to know what they didn’t need to know.
You don’t need to be informed about everything. Strategic ignorance protects your cognitive capacity for what truly requires your attention.
Ask yourself: “What information am I consuming that doesn’t improve my decisions or outcomes?” Then stop consuming it.
5. Use Energy Management, Not Time Management
Stop thinking about your day in terms of available hours. Start thinking about your cognitive capacity throughout the day.
Schedule demanding cognitive work when your bathtub is emptiest. Save routine tasks, meetings, and administrative work for when you’re depleted. Match task difficulty to cognitive availability.
The Confidence Connection
Interestingly, Poumpouras linked the bathtub theory directly to confidence. When asked how confident people differ from others, she pointed to decision-making and cognitive load management.
“Confident people are okay with not knowing all the information,” she said. “They don’t need to know everything.”
Insecurity fills your bathtub with unnecessary water. The need to know everything, understand every angle, analyze every possibility, and prepare for every contingency stems from fear and insecurity. It overwhelms your cognitive capacity and ironically makes you less capable of performing well.
Confident people trust their ability to handle situations as they arise. This trust allows them to keep their bathtub light, preserving mental resources for what actually matters.
The Professional Application
In professional contexts, the bathtub theory explains several common workplace dynamics:
Why meetings are so draining: Each meeting requires context switching, forcing you to fill your bathtub with new information, relationships, and decisions.
Why “always on” culture destroys productivity: Constant availability keeps your bathtub perpetually full, leaving no capacity for deep work.
Why busy leaders make poor decisions: Their bathtubs are so full that decision quality deteriorates.
Organizations that understand cognitive load create systems that protect their people’s mental capacity. They minimize unnecessary decisions, reduce meetings, eliminate busywork, and respect focus time.
The Bottom Line on Cognitive Load
The bathtub theory offers a deceptively simple framework for a complex challenge. Most people will never become president or operate at that level of pressure. But everyone faces cognitive load constraints.
The question isn’t whether you have a bathtub—everyone does. The question is: Are you managing what goes into it?
As Poumpouras observed from watching some of the world’s most effective leaders: excellence requires subtraction, not addition. Keep your bathtub light. Protect your cognitive capacity. Make fewer, better decisions.
“Think about all the decisions he had to make every single day,” Poumpouras said of President Obama. “I want a light bathtub. Take that thing out. Lighten your bathtub.”
The path to better decisions, lower stress, and higher performance doesn’t require adding more to your life. It requires ruthlessly protecting your most valuable resource: the limited capacity of your cognitive bathtub.
Key Takeaways
- Your brain’s cognitive capacity is finite—like a bathtub that overflows when overfilled
- Presidents keep their “bathtubs light” by eliminating unnecessary decisions
- Decision fatigue leads to poor choices and sloppy performance
- Excellence requires subtraction, not addition to your cognitive load
- Confident people accept not knowing everything to preserve mental resources
- Protect morning hours when cognitive capacity is highest
- Strategic ignorance is a strength, not a weakness
Former Secret Service Agent Evy Poumpouras’s observations, shared on The Diary of a CEO podcast with Steven Bartlett, reveal how the world’s most effective leaders think about mental resources. Apply the bathtub theory to your life, and you’ll make better decisions with less stress.