The Goldilocks Rule: How to Stay Motivated in Life and Business Why do we stay motivated to reach some goals, but not others?

It was 1955 and Disneyland had just opened in Anaheim, California when a ten-year-old boy walked in and asked for a job. Labor laws were loose back then and the boy managed to land a position selling guidebooks to visitors for $0.50 a piece.

Within a year, he had transitioned to Disney's magic shop where he learned tricks from the older employees. He experimented with jokes and tried out simple magic routines on the visitors. Soon, he discovered that what he loved was not performing magic, but performing in general. The young boy set his sights on becoming a comedian.

Once he entered high school, he started performing in small clubs around Los Angeles. The crowds were small and his act was short. He was rarely on stage for more than five minutes. In one case, he literally delivered his standup routine to an empty club.

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It wasn't glamorous work, but there was no doubt he was getting better. His first magic routines would only last one or two minutes. By high school his material had expanded to include a five minute skit and then a ten minute show. At the age of 19, he was performing weekly at clubs for twenty minutes at a time. Of course, he had to read three poems during the act just to make the routine long enough, but still. He was improving.

He spent another decade experimenting, adjusting, and practicing his act. He took a job as a television writer and, gradually, he was able to land his own appearances on television shows. By the mid-1970s, he had worked his way into being a regular guest onThe Tonight Show and Saturday Night Live.

After nearly 15 years of work, he broke through to wild success. He toured 60 cities in 63 days. Then 72 cities in 80 days. Then 85 cities in 90 days. 18,695 people attended one show in Ohio. 45,000 tickets were sold for his 3-day show in New York. He catapulted to the top of his genre and became one of the most important comedians of his time.

His name was Steve Martin.

How to stay motivated

I recently finished Steve Martin's wonderful autobiography, Born Standing Up.

Comedy is not for the faint of heart. It is hard to imagine a situation that would strike fear into the hearts of more people than failing to get a single laugh on stage. And yet, Martin worked at it for 18 years. In his words, "10 years spent learning, 4 years spent refining and 4 years spent in wild success." His story offers a fascinating perspective on motivation, perseverance and consistency.

Why do we stay motivated to reach some goals, but not others? Why do we say we want something, but give up on it after a few days? What is the difference between the areas where we naturally stay motivated and those where we give up?

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Scientists have been studying motivation for decades. While there is still much to learn, one of the most consistent findings is that perhaps the best way to stay motivated is to work on tasks of "just manageable difficulty."

The Goldilocks Rule

Human beings love challenges, but only if they are within the optimal zone of difficulty.

For example, imagine you are playing tennis. If you try to play a serious match against a four-year-old, you will quickly become bored. The match is too easy. On the opposite end of the spectrum, if you try to play a serious match against a professional tennis player like Roger Federer or Serena Williams, you will find yourself demotivated for a different reason. The match is too difficult.

Compare these experiences to playing tennis against someone who is your equal. As the game progresses, you win a few points and you lose a few points. You have a chance of winning the match, but only if you really try. Your focus narrows, distractions fade away and you find yourself fully invested in the task at hand. The challenge you are facing is "just manageable." Victory is not guaranteed, but it is possible. Tasks like these, science has found, are the most likely to keep us motivated in the long term.

Tasks that are significantly below your current abilities are boring. Tasks that are significantly beyond your current abilities are discouraging. But tasks that are right on the border of success and failure are incredibly motivating to our human brains. We want nothing more than to master a skill just beyond our current horizon.

We can call this phenomenon The Goldilocks Rule. The Goldilocks Rule states that humans experience peak motivation when working on tasks that are right on the edge of their current abilities. Not too hard. Not too easy. Just right.

Martin's comedy career was a perfect example of what The Goldilocks Rule looks like in the real world. Each year, the length of his comedy routines expanded, but only by a minute or two. He was always adding new material, but he also kept a few jokes that were guaranteed to get laughs. There were just enough victories to keep him motivated and just enough mistakes to keep him working hard.

Measure your progress

If you want to learn how to stay motivated to reach your goals, then there is a second piece of the motivation puzzle that is crucial to understand. It has to do with achieving that perfect blend of hard work and happiness.

Working on challenges of an optimal level of difficulty has been found to not only be motivating, but also to be a major source of happiness. As psychologist Gilbert Brim put it, "One of the important sources of human happiness is working on tasks at a suitable level of difficulty, neither too hard nor too easy."

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This blend of happiness and peak performance is sometimes referred to as flow, which is what athletes and performers experience when they are "in the zone." Flow is the mental state you experience when you are so focused on the task at hand that the rest of the world fades away.

In order to reach this state of peak performance, however, you not only need to work on challenges at the right degree of difficulty, but also measure your immediate progress. As psychologist Jonathan Haidt explains, one of the keys to reaching a flow state is that "you get immediate feedback about how you are doing at each step."

Seeing yourself make progress in the moment is incredibly motivating. Steve Martin would tell a joke and immediately know if it worked based on the laughter of the crowd. Imagine how addicting it would be to create a roar of laughter. The rush of positive feedback Martin experienced from one great joke would probably be enough to overpower his fears and inspire him to work for weeks.

In other areas of life, measurement looks different but is just as critical for achieving a blend of motivation and happiness. In tennis, you get immediate feedback based on whether or not you win the point. Regardless of how it is measured, the human brain needs some way to visualize our progress if we are to maintain motivation. We need to be able to see our wins.

Two steps to motivation

If we want to break down the mystery of how to stay motivated for the long-term, we could simply say:

1. Stick to The Goldilocks Rule and work on tasks of just manageable difficulty.
2. Measure your progress and receive immediate feedback whenever possible.

Wanting to improve your life is easy. Sticking with it is a different story. If you want to stay motivated for good, then start with a challenge that is just manageable, measure your progress and repeat the process.

James Clear writes at JamesClear.com, where he shares science-based ideas for living a better life and building habits that stick. To get strategies for boosting your mental and physical performance by 10x, join his free newsletter.

This article originally appeared on JamesClear.com.