A couple of weeks ago, Microsoft CEO Satya Nadella gave us a glimpse into how successful leaders think. His advice: "Don't be a know-it-all; be a learn-it-all."

Cognitive psychologists are finding that there's a lot of truth to that statement. They say that overcoming--or at least being aware--of some our inherent biases is the key to excelling in life and in business.

One bias in particular is gaining more attention: People who perform the worst in a particular skill often overestimate their own competence in that skill.

I first noticed this phenomenon among public speakers about 15 years ago when I interviewed business leaders on television. I asked one expert if she'd like to practice some questions ahead of time to prepare for an interview.

"Do you know how many shows I've been on? I've got this," she shot back.

I'll never forget what happened next. The guests' answers were long and convoluted. It was a terrible interview. The producer yelled in my earpiece, "Don't ever book this person again!"

Two weeks later I interviewed one of the most famous financial television personalities at the time. Suze Orman would later become one of Oprah's favorite guests because she was so skillful at simplifying complex topics. After the interview she turned to me and asked, "How did I do? Do you have any tips for next time?" Now I know that Orman was great because she was humble.

Throughout my career as a business journalist and communication advisor, I noticed that people who say they're really good at public speaking are often mediocre at best while those who are humble and seek feedback are almost always better than average.

What's going on?

The Dunning-Kruger effect

In 1999, Cornell University psychology professors David Dunning and Justin Kruger wrote a paper titled: "Unskilled and unaware of it." They found that, in many domains, people tend to overestimate their skills. Those same people are hit with a double whammy. They are the last to notice that their lack of skills. According to the researchers, they performed poorly relative to their peers and "were utterly unaware of this fact."

I recently discussed the so called "Dunning-Kruger effect" with Dr. Philip Fernbach, a cognitive scientist at the University of Colorado's Leeds School of Business who co-authored a new book, The Knowledge Illusion. Fernbach says Dunning's research is important because all of us are unskilled in most domains in our lives. By not knowing what we don't know, it can hold us back from being our best.

Intellectual humility--recognizing that that a skill or topic is more complex than you think--is the key to unlocking one's potential.

In Humility is the New Smart, University of Virginia business professor Ed Hess and corporate attorney Katherine Ludwig say that the two big inhibitors to learning are "a preoccupation with protecting our own egos and a fear of failing." The researchers cite the work of Nobel prize-winning psychologist Daniel Kahneman, who said, "Our minds are limited by excessive confidence in what we believe we know, and our apparent inability to acknowledge the full extent of our ignorance." The 'new smart' means taking our cognitive and emotional skills to a higher level, and recognizing the biases that prevent us from excelling in our careers.

Always keep learning

Public speaking is a skill. It's an art and, like any art, there's always something new to learn. Keep learning by:

  • Soliciting feedback. Deliver your presentation in front of a diverse group of listeners. You might find that the font is too small to be read easily by the older person in the audience and the younger person doesn't like your choice of color scheme.
  • Practice. People who overestimate their presentation skill practice less because, well, they think they know the material. Everyone needs to rehearse, no matter how many times they've given presentations.
  • Try a design style. If you're like most people, you've been using the same PowerPoint template or style for years. Next time, outsource the work to design experts. There are many new styles of presentation design. See what's possible.

Your ability to persuade others through public speaking is far too important to be left to chance. Overcoming your inherent cognitive bias to think that you know more than you actually do will help you excel as a speaker and a leader.

Published on: May 5, 2017
The opinions expressed here by Inc.com columnists are their own, not those of Inc.com.