The One Thing: Summary & Review

the one thing book cover

In “The One Thing” Gary Keller’s promotes the idea that to succeed in life you need to focus on one thing in life and ruthlessly prioritize that one thing, while mostly forgetting about all the rest.

Bullet Summary

  • Focus on one important thing in your life (your one thing)
  • Prioritize daily on what will have the biggest impact on your one thing
  • Do one thing at a time

Full Summary

About the Author: Gary Keller is a successful American entrepreneur and author.
He is the founder of Keller Williams a real estate company that, at one point, was the largest real estate company in the world by agent count and second in closed sales volume, and units sold.
So, we may add, Gary Keller is speaking from experience when he talks about “focusing on your one thing”.

1. Start Out Thinking Big

Think big.

Gary Keller tells the story of how Arthur Guinness (producer of Guinness beer) and J. K. Rowling (author of Harry Potter books) embarked on their life quest with huge expectations.

Guinness leased the beer factory for 9.000 years and Rowling envisioned seven books before even starting to write the first.

Keller says they were successful in no small part because they started out with huge vision and goals (also read: The Magic of Thinking Big).

When You Think Small You Waste Your Potential

But what do most of us do instead?

We are intimidated by big thoughts and visions and we settle down for something “more realistic”. But when we settle down for “something more realistic” we lower our future trajectory and we settle down for less than we could.

Success requires action, of course. But action requires thought. That’s why we need to think big.

Success requires action; but action requires thoughts: Think BIG!

2. Prioritize Your Tasks: Pareto Principle

Many of us have either done or gone through a task list at one point or another in our lives.

The One Thing makes a great point on common mistakes when starting said task lists: tackling the easiest first, the first on the lists or the most time-consuming.

That’s a big mistake because not all tasks are the same.

Some won’t do much of a difference if at all, while some others can provide you with a quantum leap towards your goals.

That’s why we should all ruthlessly prioritize our tasks by the impact they will have on our goals.

Here’s the question to achieve just that:

What’s the ONE thing I can do, such that by doing it everything else will become easier or unnecessary?

And that’s exactly the principle behind The One Thing:

3. The One Thing & The Focusing Question

That simple question right there will do two things for you:

  1. Remind you of the one thing, your overarching goal you are after (long term)
  2. Help you prioritize in the short term what you need to do

4. Habits: The Key to Success

Keller says that staying steadfast in the pursuit of your goal is not so much self-discipline as it is about habits.

Think of Michael Phelps, he says. He was diagnosed with attention deficit hyperactivity disorder. Such as, that he wasn’t able to focus on just one thing.

Instead, he focused on just one thing: swimming every day.

My Note:
ADHD is a rather common diagnosis these days and not nearly as a handicap as The One Thing makes it out to be. However, the point is still valid.

Keller righteously says that once the habit has been formed it won’t take nearly as much discipline to maintain it. And after it becomes an established part of your life, you can go back to “cruise control” or, even better, focus on building another empowering habit (also read The Power of Habit).

I like this quote on the subject:

Hard habits are difficult to build but make for an easy life. Easy habits don’t require any effort but make for a hard life.

Brian Tracy

5. Focus on The One Thing (until it’s done)

Multitasking is not something to be proud of: multitasking saps our efficiency.

We can do a few things at the same time, yes, but one of those activities should be very easy. Like walking (doesn’t require focus) and talking complex issues on the phone (we can fully focus on the issues).

But talking about complex issues while writing on another complex issue does not work. We cannot multitask with two activities that require our full focus and attention… Unless we do both of them very sloppily.

Also, as Ferris says in The 4 Hour Workweek, we don’t work like computers CPU work and switching from one activity to another take time to re-adjust and we waste valuable time.

“Wasting time” doesn’t sound impressive enough to you?

Well, just think this: it’s estimated that office workers, interrupted on average every 11 minutes, spend one-third of the day recovering from distractions!

Don’t waste a third of your day: focus on one thing at a time.

My Note:
while Keller is spot-on on multitasking, don’t let that discourage you from looking at all ways you can become more efficient. For example, when I am doing repetitive tasks on my laptop I do listen to audiobooks (for example: adding affiliate links on this page).
And when I’m doing easier tasks such I might listen to easier Youtube videos.

6. Pay Attention (And Conserve) Your Willpower

Your willpower is like a fuel tank. It will run out after you’ve run with it for a long time.

It’s a phenomenon called ego depletion.

Keller says you must work with that in mind to be efficient: choose carefully what you need to pay attention to and do the most important things first.

My Note:
I prefer the analogy of willpower as a muscle as it can also grow over time. Also the notion that willpower is limited has been challenged and you can read more in my pop-psychology article.

7. Focusing on One Thing Means Saying No To Many Others

To focus on your one thing you must learn to say no to many more other projects and opportunities.

If you receive too many requests, think of ways to reduce them, or learn to say no without sounding mean about it. Bottom line is, you gotta say no to say yes to your one thing.

Also read:

Assertiveness: 6 Steps to Empowered Communication

8. Visualize The Process

These days everyone talks about the importance and usefulness of visualizing.

I liked though that Keller adds a further step to it: don’t just visualize your goal, but visualize the steps that will get you there.

Students who visualized themselves studying VS students who just visualized getting top grades reported higher levels of satisfaction while studying.

9. Let Chaos Pile Up

Keller says that as you focus on one thing your life will keep happening in the meanwhile. He says that, at a certain point, you should come to accept chaos as an inevitable part of life.

My Note: this resonated with me a lot as I read it.

I always used to feel bad about my house not being perfectly clean. Well, now I know that it’s a normal part of focusing on knowledge acquisition instead.

the one thing book cover

Real Life Applications

  • Ruthless Prioritization

This is something that I’m really sold into.

I had a mindset where I often would keep my best moves for the future. That way I could lull myself in the idea that “the best is yet to come”. BS. Life is short, always ask yourself what’s the biggest bang for the buck you can do right now.

  • Accept Some Chaos While You Purse Your One Thing

When you focus on one thing you know that you can expect other areas of your life to suffer. It’s OK.

This was a very important concept for me and now I accept more openly that, well, my house won’t be as perfectly clean as I like it to be.


Starting With Huge Vision?

The author picks a few examples to make the point you must start with huge vision. But that does not prove the effectiveness of the method (it’s a typical case of inductive reasoning fallacy, also read Fooled by Randomness).

I can think of as many people who started with big dreams and got crushed by a much harsher reality than they expected.

As a matter of fact, I think that envisioning a huge goal come true before you even start can be dangerous because the first drawbacks can discourage you.

As Keller himself says, better to also focus on the hard work to get there. And as The One Thing itself quotes: the secret to getting ahead is getting started (even if you don’t have your grand vision yet).

The secret to getting ahead is getting started


It Makes Sense: To Succeed In A Highly Competitive World, You Must Focus On One Thing

The One Thing is somewhat of a happy crossover between Grit by Angela Duckworth (stay with one thing) and Start with WHY by Simon Sinek (find your one thing).

To which Keller adds ruthless prioritization.


The One Thing is a great book.
Lots of wisdom and lots of sensible information to live a fulfilling and successful life.

It’s a five-star book (but I give it four stars here because I am adamant about keeping my 5 stars to a very limited number of books).

Read more summaries or get the book on Amazon

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