You’re good.

You could be better.

Consider a skill you've developed: Business, sports, personal, anything. At first you were terrible.

Terrible is a great place to start because improving on terrible is easy. With a little practice you turned terrible into mediocre.

And you had fun, because improvement is fun.

Then with a lot more practice—practice that started to be a little less fun—you got even better.

Now you’re good. Maybe you’re even really good.

But you’re not great. And somewhere along the way you stopped improving, stopped having fun, and started to think you weren’t capable of being great.

Why did you stop improving and stop having fun? Hitting the wall wasn't due to a lack of effort, or willpower, or even talent. You stopped improving because of the way you applied your effort and willpower.

Say you’ve developed reasonable proficiency at a physical skill. Take golf. At first every swing of the club felt awkward, but you gradually found a groove. You started to think less. You quit thinking about your hips. You quit thinking about the height of your back swing. You quit thinking about what your wrists do in your follow-through.

You started thinking less because your skills became more automatic. In some ways that's a great sign: Automatic means you internalized a skill.

But automatic is also a bad sign. Anything you do automatically, without thinking, is really hard to adjust. To get better you must find ways to force yourself to adapt and modify what you already do well.

Here are four ways to force yourself to adapt—and in the process rediscover the joy of improving:

Go fast. Force yourself to perform a task more quickly. You’ll make mistakes; probably lots of them. Don't get frustrated. The more mistakes you make the better, because the best way to learn is from making mistakes. If a product demo usually takes 10 minutes, fly through it in five. (As a practice run, of course.) You’ll break free from some old habits, adapt to the faster speed, and find ways to make a good presentation even better.

Go slow. Take your time. Take too much time. Swinging a golf club in slow motion allows you to feel muscles working that you normally don’t notice. Taking more time to run through your sales pitch will uncover opportunities to highlight additional customer benefits. Going slower is a great way to notice habits that have become automatic—and to examine each one of them critically.

Go piece by piece. Every complex task is made up of a series of steps. Pick a step and focus solely on that step. Break a sales call into component pieces; first focus on perfecting your opening. No customer is the same, so develop modifications you can instantly apply to different scenarios. Deconstruct each step, master that step, and move on to the next one. When you put all the pieces back together your skills will be markedly improved.

March to a different drum. We all settle on ways to measure our performance; typically we choose a method that lets us feel good about our performance. So pick a different measurement. If you normally measure accuracy, measure speed instead. If you normally measure leads generated, measure conversions instead. Use video. Ask a colleague to critique your performance. Your customers, your vendors, and your employees all measure your performance differently than you do. View yourself from their perspective and you’ll easily find areas for improvement.

Think this process won’t help you excel? Consider this passage from Andre Agassi’s autobiography, Open:

Every ball I send across the net joins the thousands that already cover the court. Not hundreds. Thousands. They roll toward me in perpetual waves. I have no room to turn, to step, to pivot. I can’t move without stepping on a ball…

Every third ball… hits a ball already on the ground, causing a crazy sideways hop. I adjust at the last second, catch the ball early, and hit it smartly across the net. I know this is no ordinary reflex. I know there are few children in the world who could have seen that ball, let alone hit it…

My father says that if I hit 2,500 balls each day, I’ll hit 17,500 balls each week, and at the end of one year I’ll have hit nearly one million balls. He believes in math. Numbers, he says, don’t lie. A child who hits one million balls each year will be unbeatable.

When you try to do your best every time, every mistake you make is obvious, even if only to you. Learn from every mistake. Adapt and modify your techniques so you constantly improve.

Because when you keep improving you keep having fun—and all the focused effort you put in will once again feel worth it.