100% is Easier than 98%
A strange rule from a Harvard professor that changed how I train, eat, and build companies.
A Harvard professor once wrote something that sounds completely ridiculous:
100% is easier than 98%.
How could doing something all the time possibly be easier than doing it almost all the time?
Yet the more I think about it, the more I realize this rule quietly explains discipline, entrepreneurship, and marathon running.
I discovered this lesson the hard way while trying to break the 3-hour marathon barrier.
And strangely enough, it had nothing to do with running and everything to do with human weakness.
In marathon running, every runner usually has a unique edge.
Some are built stronger.
Some have better speed.
Some have superior endurance.
For me, my competitive edge has always been something much simpler:
Getting extremely lean before races.
In a marathon, carrying less weight over 26.2 miles pays off big time.
When I’m training seriously, I’ll drop my body fat from around 15% to the 3% range.
For many years, I could never break below 10% body fat.
Until I came across a concept from Clayton Christensen’s book How Will You Measure Your Life.
In the book he writes:
“It’s easier to hold your principles 100% of the time than 98% of the time.”
It sounds counterintuitive.
But it’s true.
So one day, while preparing for my second attempt at breaking the 3-hour marathon at the Marine Corps Washington Marathon, I decided to apply the rule to my diet.
I cut out alcohol, processed sugar, and low-quality carbs.
Not 98%.
100%.
At the beginning it was brutal.
Especially the alcohol part.
Every time I went out with friends someone would offer a beer or a glass of wine.
“Come on, just one. How bad can it be?”
But I stuck to the rule.
And something strange happened.
After a few weeks the temptation disappeared.
No debate.
No negotiation.
Just a habit.
Suddenly it was easy.
No joke: 100% became easier than 98%.
When people see that level of discipline, they assume it must take enormous willpower.
The truth is the opposite.
I do it precisely because I don’t trust my willpower.
Once the rule is absolute, the decision disappears.
The Business Version
This rule shows up everywhere in business.
Founders often try to operate at 98% commitment.
They launch a startup… but keep the safe job.
They say they want to build a great company… but still optimize for comfort.
That silent negotiation slowly kills the dream.
The most effective founders I know operate in absolutes.
They remove ambiguity.
No backup plan.
No hedging.
No “let’s see how this goes.”
Just:
We’re doing this.
Ironically, that level of commitment simplifies everything.
Decisions become clearer.
Priorities sharpen.
Energy concentrates.
Once the boats are burned, the path forward becomes obvious.
In a 60 Minutes interview Elon Musk gave perhaps the simplest founder philosophy ever:
“I don´t ever give up.”
That’s the 100% rule.
Why 98% Is So Dangerous
The real problem with 98% is the constant negotiation.
Should I have one drink?
Just tonight?
Should we pivot?
Should we keep going?
Every decision drains energy.
100% eliminates the conversation.
No debate.
No bargaining.
No exceptions.
The rule becomes the system.
And systems beat motivation every time.
Lesson Learned:
If something matters enough, make the rule simple.
100% is easier than 98%.
3-2-1 Sprint
3 Ideas
1. Remove the negotiation.
If you’re debating every decision, your system is broken.
2. Use binary rules.
No sugar. No alcohol. No quitting. Clear rules free mental energy.
3. Design your environment.
Discipline isn’t about strength. It’s about removing temptation.
2 Quotes
“It’s easier to hold your principles 100 percent of the time than it is 98 percent of the time.”
— Clayton Christensen
“If something is important enough, you do it even if the odds are not in your favor.”
— Elon Musk
Contrarian Corner
Most people don’t fail because the goal is too hard.
They fail because they operate at 98%.
Last year I got tired of eating so much refined sugar.
All year I tried moderation.
“Just a little.”
It never worked.
So this year I made a rule:
365 days with ZERO refined sugar.
The first two weeks were hell.
But now it’s been about 2.5 months.
And surprisingly…
it already feels easy.
All thanks to the 100% rule.
Sometimes the hardest rules make life the simplest.
Thanks for reading.
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