What does it take to become an expert or master performer in a given field? 10,000 hours of practice. It’s a common rule of thumb, popularized by Malcom Gladwell in his bestseller Outliers: The Story of Success. It’s catchy, easy to remember, and – more or less – completely false.

We’re debunking the 10,000 hour rule and taking a look at proven ways to practice your way to mastery.

“A provocative generalization,” is what Anders Ericsson calls the 10,000 hour rule. And it was Ericsson’s research on expert musicians that Gladwell cites as a basis for the rule. Ericsson says the rule is an oversimplification, and in many ways, an incorrect interpretation of his research. The 10,000 Hour Rule: Catchy and easy to remember, but on some pretty shaky scientific footing.

Busting the Myth of the 10,000 Hour Rule

Let’s start with breaking down the myth of the 10,000 hour rule. Gladwell uses several examples in his book when introducing this rule: one is the research done by Ericsson that focused on violin students at a music academy in Berlin. The study found that the most accomplished of the students had put in 10,000 hours by the time they turned 20. Gladwell also estimates that the Beatles put in 10,000 hours of practice playing in Hamburg in the early 1960s, and that Bill Gates put in 10,000 hours of programming work before founding Microsoft. Hence the 10,000 hour rule was born: put in your 10,000 hours of practice, and become an expert in a given field. Pretty easy, right?

But upon closer examination, problems start to emerge.

First of all, Ericsson says, the number 10,000 is totally arbitrary. It’s catchy and easy to remember, but not really based on anything substantial. It’s the number of hours these promising violinists had put in by the time they were 20 years old. By the age of 18, they had put in an average of 7,400 hours, but the 7,400 Hour Rule doesn’t have quite the same ring, does it? And even at 20, they were very good at playing the violin, and probably headed to the top of their field, but they were not yet experts.

On top of that, Gladwell misunderstood that 10,000 hours was an average, and not all the best violinists had put in this number by age 20. In fact, half of the best hadn’t put in 10,000 hours.

Hmm. That’s definitely concerning, but are we sure that the 10,000 rule isn’t true? It sure seems like plenty of hours to master something. And if it isn’t true, what do we know about practice and how to master a craft?

Well a few things we know for sure are that not all practice is created equal – and not everyone starts from the same place.

10,000 Hours of What? All Practice Isn’t Equal

If you wanted to get better at shooting a bow and arrow, would it be the same thing to experiment on your own for 3 hours as it would be to practice with an expert for 3 hours, who is giving you tips on form and technique and getting better? The answer is self-evident, right? And this is one of the biggest flaws of the 10,000 Hour Rule: It focuses on the amount of time spent practicing, and not the quality of that practice – and not all practice is equally helpful.

Gladwell doesn’t differentiate between different types of practice, even though it’s a really important distinction. The best way to get better at something is through something known as deliberate practice, which basically means practicing in order to get better: doing activities recommended by experts to develop specific abilities, identifying weaknesses and working to correct them, and intentionally pushing yourself out of your comfort zone. “This distinction between deliberate practice aimed at a particular goal and generic practice is crucial,” Ericsson says, “because not every type of practice leads to improved ability. You don’t get benefits from mechanical repetition, but by adjusting your execution over and over to get closer to your goal.” 

Deliberate practice is often guided by an expert, skilled coach, or mentor, “someone with an expert eye,” according to bestselling author Daniel Goleman. These coaches and mentors are offering feedback on specific ways to improve, and “without such feedback, you don’t get to the top ranks. The feedback matters and the concentration does, too – not just the hours.”

So does the 10,000 rule hold up if it’s 10,000 hours of deliberate practice with experts? No, it still doesn’t. There are still a lot of other variables at play.

The Great Debate Continues: Nurture Has Its Limits

A recent meta-analysis by Case Western Reserve University psychologist Brooke Macnamara and her colleagues found that deliberate practice and skill are related – but far from perfectly related. Deliberate practice hours predicted 26% of the skill variation in games such as chess, 21% for music, and 18% for sports. This is the second biggest flaw of the 10,000 Rule: It leads to a misconception that anyone can become an expert in a given area by putting in the time. But clearly, since deliberate practice hours predicted only 20-25% of skill levels, there are other factors at play.  Researchers have been able to pinpoint a few of them, including age and genetics.

The age at which someone gets involved in an activity seems to play a role. As with language learning, there may be a window during childhood when specific, complex skills are most easily acquired. Cognitive psychologists Fernand Gobet and Guillermo Campitelli found that chess players who started early reached higher skills levels as adults than those who started later, even after taking into account differences in deliberate practice hours.

Of course, genetics play a role as well. A lot of the best research on the role of genetics in acquiring certain abilities comes from studying – you guessed it – twins. Psychologist Robert Plomin led research at King’s College London that found more than 15,000 twins in the United Kingdom and had them perform a series of tests and fill out questionnaires – and some of the findings are quite remarkable. Identical twins’ drawing ability was much more highly correlated than fraternal twins’ drawing ability. Since identical twins share 100% of their genes, whereas fraternal twins share only 50%, these findings indicate that differences between people in basic artistic ability is at least in part due to genetics. Using the same data set, over half the variation between skilled and less skilled readers was found to be due to genetics. Clearly, the number of hours two people will need to put in to master a skill will be different depending on their genetic disposition.

And that wasn’t the only finding indicating that we have a genetic predisposition to excel in some areas more than others. Psychologist Miriam Mosing of the Karolinska Institute in Sweden has led fascinating experiments with more than 10,000 twins that tests their basic music abilities, like whether two melodies carry the same rhythm, in relation to how much they have practiced music. What they found is that while genes influenced 38% of the musical abilities they measured, no evidence was found that the amount of practice influenced those abilities. That is to say, an identical twin who practiced music regularly was not any more likely to be good at these abilities than the identical twin who did not practice. This doesn’t mean there’s no point in practicing music. There are certainly music skills that you can improve with practice, like reading music and playing a keyboard. But it does indicate that there are limits to the power of practice. Not everyone could become an expert violinist even with 10,000 hours of practice – and I think I am one of those. There is some innate ability necessary to become a master in a field.

Malcolm Gladwell got one thing right, without a doubt: it takes many years of concerted effort and practice to become a true expert in a field. But while the time spent practicing is important, it is far from the only factor. Your genetic makeup, when you start, and how you learn all combine to determine how many hours it would take you to master a specific craft.

Consider the research of master chess players by those cognitive psychologists, Fernand Gobet and Guillermo Campitelli. They found that there were actually huge differences in the number of hours of practice it took chess players to reach a specific skill level. The number of hours to reach “master” status ranged from 728 hours to 16,120 – meaning some players needed 22x more practice hours than others to reach the same skill level. Not so surprising now, huh? And even more reason to be skeptical of the 10,000 hour rule.

Let’s rename it the 728 to 16,120 Hour Rule.

And when we get into skills that are less easily measurable than chess or sports, we may have to scrap the concept of practice hours altogether…

From 10,000 Hours to 10,000 Experiments

The meta-analysis discussed above, led by Brooke Macnamara, compared deliberate practice and acquired skills, and found that deliberate practice predicted 26% of performance in games such as chess, 21% for music, and 18% for sports. But what about fields that are less tangible? Learning how to play a guitar or how to shoot a soccer ball are tangible skills, with well-established “norms” for what mastery looks like, or sounds like. But what about practicing less tangible skills, like being a good boss or a good parent?

The study found that deliberate practice predicted even less of the performance in these areas, predicting only 4% of the variance in performance in education, and less than 1% for professions. Woah.

It’s crazy, but it also makes sense. You could be a pretty terrible boss for 10,000 hours – putting in the hours but not mastering the craft by any means. And what’s more is that there is not exactly a clear idea of what being a successful leader even looks like. The skills required for successful leadership are changing in today’s rapidly changing world. In that context, what does it take to become a master or expert? It requires a new way of thinking about practice altogether. In these areas, we may want to replace the 10,000 hour rule with the 10,000 experiment rule.

The 10,000 experiment rule, first coined by Medium, requires taking the scientific method – develop a hypothesis, test it out, analyze the results, develop another hypothesis – and using it in every day life. Deliberate experimentation has a lot in common with deliberate practice – the goal is to get better by developing crucial skills – but the means is different. It’s less rigid (“This is how you get better at this”) and more agile (“I wonder how this would work”).

If you want to master these less tangible skills, you need to develop what Stanford’s Carol Dweck calls a growth mindset, and infuse it into your deliberate experimentation. A growth mindset is the ability to learn from your mistakes and treat them as opportunities for growth. That way, every experiment you run is super valuable. Even if your hypothesis is incorrect, you will have learned something from it, and can use that to keep growing. That is the type of practice that will help you be successful in rapidly changing environments where success looks different today than it did in the past, or will in the future.

The 10,000 hour rule is a myth. If you want to master something tangible like chess or basketball, practice deliberately in the smartest way you can, and don’t worry about how long it takes – or assume that if you just put in the time, you will master it.  And if you want to master a less tangible skill, go with deliberate experimentation, and infuse it with emotional intelligence.