The ONE Thing: The Surprisingly Simple Truth Behind Extraordinary Results by Gary Keller

Reading Time: 7 minutes


Business coach and author Gary Keller provides a simple and powerful framework for achieving extraordinary results in your personal and professional life. He shows you how to leverage a powerful question to live a life of purpose, priority, and productivity. Above all else, you’ll walk away with greater clarity on how to create a life worth living.

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Key Takeaways

The ONE thing

One thing is at the heart of every success. It’s your job to find and pursue your one thing.

Six lies of success

Everything matters equally

  • Equality is an idea, not a practical reality in the world of results.
  • To-do lists can tyrannize your days with tasks if you don’t vet them. You feel an obligation to do everything on the list, rather than the things that really matter. You should have a “success” list, rather than a to-do list.
  • Achievers have an eye for the essential.
  • Live a life focused on the vital few things that matter rather than the trivial many. Pareto’s law of 80% of outputs are driven by 20% of inputs is a predictable law of nature, not just an interesting theory.


  • People think they can multitask, but they can’t. We may be able to do multiple things at once, but we can’t focus on two things at once. Multitasking is ineffective and inefficient
  • It also leads to constant task switching, which costs you valuable energy, time and efficiency.

A disciplined life

  • There’s a common idea that success requires you to be disciplined at all times. The reality is that no one is or can be disciplined all the time.
  • What you really need is the discipline to build a habit, which on average, takes 66 days to build. Once you form the habit, the action or behavior becomes a near-automatic part of your life and doesn’t require as much discipline or cognitive energy to keep up.
  • So if you have the discipline to build the right habits, you’ll start having your life work for you, rather than against you.


  • There is an idea that you can tap into your willpower at any time you want. So if you don’t feel like doing something, you just invoke your willpower and it’s okay. But this is a faulty idea because willpower is a finite resource. It’s like a power bar on your cellphone – a limited and renewable resource that needs to be managed.
  • When your willpower runs out, you revert to your default settings. That’s why at the end of a day of hard work you’re more likely to grab a bag of chips over an apple. You may know that you want the apple for your health, but your willpower is depleted and you know longer have a strong defense mechanism against the salty chips.
  • There are many ways that your willpower is taxed throughout the day, including:
    • Implementing new behaviors
    • Filtering distractions
    • Suppressing emotions
    • Restraining aggression
    • Suppressing impulses
    • Coping with fear
    • Trying to impress others
    • Doing something you don’t enjoy
    • Choosing the long term over the short term
  • You must learn to manage your willpower. For example, do your “one thing” early in the morning when your tank of willpower is still full.

A balanced life

  • Living a balanced life is a misleading concept. What you want is to seek purpose and meaning, not balance. Balance is not all bad, but if you pursue success in certain realms, it naturally comes at the expense of other things. When this happens, you need to make sure the cost isn’t too high by keeping some semblance of balance in the other areas you care about.
  • When you’re juggling the balls of life, you realize that “work” is a rubber ball that bounces back if you mess up and drop the ball. On the other hand, “family,” “health,” “friends,” and “integrity” are like glass balls. When you drop them, the consequences are higher.
  • When it comes to work, treat it as a skill you want to develop until you achieve mastery. Deprioritize everything else with work. With the other areas of your life, make sure you’re giving something to each of them.

Big is bad

  • Going big in your life is not a bad thing. If you believe in this myth, then small thinking will prevail in your life. Big is a good thing. Big is about who you can become and the bold ideas that reflect your exciting future.
  • What you build today will either: Empower or restrict you tomorrow; serve as a platform for the next level of success or a box trapping you where you are.
  • To live a great life, you need to think big. Ask bigger questions. Avoid incremental thinking. Adopt a growth, not a fixed mindset.

The focusing question

The questions you ask matter:

  • Voltaire: “Judge a man by his questions, rather than his answers.”
  • Sir Francis Bacon: “A prudent question is one half of wisdom.”
  • Gandhi: “The power to question is the basis of all human progress.”

The question you need to ask for everything is simple and deceptively powerful:

“What’s the one thing I can do such that by doing it everything else will be easier or unnecessary?”

When you consistently ask and answer the focusing question, your actions become a progression of doing one right thing after another. You focus on the one thing that matters, dig deep, and complete actions that provide the most leverage for your success.

The success habit: powerful questions and answers

For every area of your life – career, finances, leisure, learning, relationships, and health – identify the one thing on a certain time scale that you will do by answering the following question consistently:

For my [career, finances, leisure, learning, relationships, and health], what’s the one thing I can do [today, this week, this quarter, this year, in the next 5 years] such that by doing it everything else will be easier or unnecessary.

Make your question big and specific. For example, “What’s the one thing I can do to double sales in 6 months such that by doing it everything else will be easier or unnecessary?”

There are three types of answers to your big and specific question:

  • Doable → realistic and probable, more like a to-do list item to check off
  • Stretch → within reach, but at the end of the range and will push you
  • Great → beyond natural grasp, requiring you to go beyond your comfort zone and explore what’s possible.

If you want to be successful, choose great answers.

Live with purpose

Your purpose is your guiding force. It’s the combination of where you’re going and what’s important to you. Your purpose determines your priority, which then determines the productivity of your actions.

Without purpose, you’re stuck in the unfulfilling cycle of pursuing, acquiring, and achieving. You’re never satisfied and always looking for the next marker of success.

There are 5 factors for happiness:

  • Positive emotion and pleasure
  • Achievement
  • Relationships
  • Meaning
  • Engagement

Meaning and engagement are the most important for your happiness. When you are engaged with and find meaning in what you do, you experience a powerful and enduring happiness.

With purpose, clarity comes faster, and when things don’t go your way, you’re more resilient. To start understanding your purpose, ask yourself:

“What’s the one thing I can do in my life that would mean the most to me and the world such that by doing it everything else will be easier or unnecessary?”

What drives you? What keeps you going? Even if you aren’t sure, pick a direction and start learning. You can always change your purpose.

Live by priority

Priority is what you do now to get where you want to go. Your priority is the most important action you do to fulfill your purpose.

There are a few problems with how we think about priority:

  • Hyperbolic-discounting: the farther away a reward is in the future, the smaller is our immediate motivation to achieve it. This bias for present rewards limits our future results.
  • Planning fallacy: Overconfidence leads us to overestimate what we can achieve in a certain amount of time.

Writing down your priority is essential. People who write down goals are 39% more likely to achieve them, and those who share progress on their goals with friends, are 76% more likely to achieve them.

Live for productivity

Success is born in productivity. There are a few ways to be more productive, the most important of which is time blocking three things:

  • Time off – plan your vacation in advance, so that work comes in between vacations, rather than a vacation being a temporary release from work.
  • One thing – design your day so that you complete your one thing. Block off 4 hours to do this when it’s best for you, which is typically in the morning.
  • Planning time – Conduct a daily, weekly, quarterly, and annual review to check in on what your one thing is and to make sure that you’re setting yourself up to succeed.

Protect your time for the one thing: When someone asks you to do something that doesn’t align with your priority, protect your time. Often, it’s not as urgent as you think. Perhaps say something like, “If I get it done by [x] date, is that okay for you?”

3 commitments

Adopt a mastery mindset

Mastery is a never-ending process of deliberate practice. Decide what you want to master, and put in the work.

Seek the best ways to do things

The best of the best are committed to improving how well they do things. Extraordinary results require doing things differently. When you hit the “okay” plateau where you are competent, don’t stop there because it’s comfortable. Seek to become the best at the task at hand.

Be accountable for your one thing

You’re either accountable or not. Accountable people overcome challenges, solve problems, get results. Be accountable. Find an accountability partner who can hold you to high standards, provide objective feedback, and brainstorm when you need it.

4 productivity thieves

Inability to say no

Life presents endless requests for your time. You can’t say yes to everything, and you shouldn’t. Your responsibility is to say yes to your one thing. There may be many reasons you fear saying no, but you need to find systems to learn how to say no and be comfortable with it.

Fear of chaos

When you say yes to your one thing, that often comes at the expense of doing the endless list of things that you feel you need to do. If you’re used to trying to do everything, you might fear what happens when you let some things go. But getting comfortable with letting a few small bad things happen so that you can focus on the one thing that truly matters is essential to your success.

Poor health habits

You will not have the energy or ability to succeed if you don’t take care of your health. You need to protect your most valuable asset, yourself. Meditate, exercise, take breaks, sleep, and so on. Do whatever it takes to keep yourself in good health.

An environment that doesn’t support your goals

Every day, who you are around and what you experience determine your destiny. Surround yourself with negative people, and that attitude will rub off on you. You think, act, and become like the people you spend the most time with. Surround yourself with positive, driven, smart, and successful people. Design your working environment so that you can focus on your one thing.

Live a life of no regrets

A life worth living is a life of no regrets. The 5 most common regrets people have are:

  • Not giving themselves permission to be happier
  • Failing to stay in touch with friends
  • Not having the courage to express their feelings
  • Working too hard
  • Not have the courage to live life for themselves versus for the expectations of others

Don’t get to your deathbed with any regrets. It’s not worth it.

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