5 Words Successful (and Happy) People Never Use The biggest difference between people like us and people who do things we would like to do is they didn't reflexively decide to put up their own barriers.

LinkedIn Influencer, Jeff Haden, published this post originally on LinkedIn.

I carried my board back onto the beach. "I could never do that," a man walking by says. "I'd be too scared."

"Sure you could," I think as he walks away. Paddleboarding is hard but not that hard. First you fall off. Then you fall off some more. But soon you get better. And what's to be afraid of? You get wet and climb back on. Except for some occasional embarrassment, the downside is no greater than that of jumping in a swimming pool.

And very soon paddleboarding is relatively easy... and if it's easy for a nonathletic guy like me it can be easy for anyone.

You just have to be wiling to try.

I walked offstage after speaking to 4,500 people. A sound tech shakes his head. "I could never do that," he says.

"Sure you could," I think. It's hard, but not that hard. First you struggle because you haven't figured out what you might want to say doesn't matter -- all that matters is what your audience will benefit from hearing. Then you work and revise and find your hook and your story. And you practice. And what's to be afraid of? That you'll fail? Sometimes we bomb when we speak to one person; the only difference is the degree.

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And in time speaking is relatively easy... and if it's relatively easy for someone as shy and insecure as me, it can be fairly easy for anyone.

You just have to be willing to try.

I climbed, stiff-legged and sore, off my bike after riding 92 miles and climbing four mountains complete the inaugural Alpine Loop Gran Fondo. "That was impressive," a volunteer says as he hands me a water bottle. "I could never do that."

"Sure, you could," I think. It was hard, but it was mainly just a question of putting in the miles. First you ride 3 or 4 miles. Then 10 or so. In time you work up to 25-mile rides, then 50s. And occasionally you throw in a longer ride.

Months of training later (in my case a little less than four), you can finish a tough gran fondo... even if you're a bird-legged old guy who initially possessed the speed, power, and cardio fitness of a possum.

You just have to be willing to try.

Life throws up enough barriers. Genetics. Education. Intelligence. Athletic ability.

The list of reasons we can't do certain things is endless. No matter how hard I work I'll never be as talented as LeBron James. Or Allyson Felix. Or Serena Williams. Or Stephen King or Stephen Hawking or Stephen Colbert.

They're all bigger, stronger, faster, smarter, more creative, or much funnier. The barriers I need to overcome to achieve that level of talent are likely likely impossible to overcome. I can go far…but probably not that far.

But then there are the hundreds of barriers we construct all on our own without any justification. We don't know we can't; we just decide we can't. So we decide we shouldn't.

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We decide whatever we might want to do is too hard, too challenging, or too scary for someone like us.

And that's why five of the worst words you can ever say are, "I could never do that."

Because, in almost every case, you can. Maybe not to a world-class level, but definitely to a high level. The biggest difference between people like us and people who do things we would like to do is they didn't reflexively decide to put up their own barriers. They didn't automatically decide they can't.

Instead they just decided to try…and then keep trying.

Granted we may never become Steve Jobs. Or Mark Cuban or Richard Branson or Sara Blakely. The barriers to reaching their level of success may be too high.

But you can still be a better you than you currently think possible. You can still achieve amazing things…and average things…and silly, frivolous things that have meaning only to you.

All you have to do is decide to try.

And once you decide to try one thing, you'll quickly find you no longer put up those barriers to any other things you "can't" do. You'll be too busy enjoying all the things it turns out you can do, and dreaming up more things to try.

Think about it this way. You can't always control your level of success, but you can control whether you take the first step towards any level of success: deciding to try.

(And just in case you didn't get the point: I'm definitely nothing special, so if I can occasionally do somewhat challenging or interesting things, imagine what you can do... if you just try.)