3 mental truths all high performers embrace, says best-selling author and leadership coach

It's no question that today's workplace looks very different than it did decades ago. It's faster, more flexible, inclusive and purpose-driven. The fundamental rules about how to be a high performer, however, remain unchanged.

In my book, "8 Steps to High Performance: Focus on What Matters (Ignore the Rest)," I explain how to how to optimally apply your time and effort to boost your performance. In order to become a high performer, especially if you're looking to make positive changes as you enter a new year, it's critical to understand the mindset of a high performer and the three truths that they embrace:

Occasionally, I hear the cry, "I work smart, not hard! I get as much done in 40 hours as others do in 60 hours!" That may be true, but it doesn't always lead to high performance. When people say they excel at being efficient, they often mention avoiding social activities, like chatting with others in the breakroom or frequently working from home to avoid office distractions. While these behaviors may make someone more efficient during work hours, they're not necessarily building the important relationships they will need to succeed and advance in their careers.

What's more, accomplishing the same amount of work in less time than your coworker doesn't always make you a high performer, it just means you're efficient. If you delivered anything more than the average performer, you're just a very fast average performer. True high performers may finish their work faster than others, but they'll then spend the 15 hours they just saved contributing to other things, like pitching in on an understaffed project or having a coffee with a peer to build a better relationship. Their standard isn't to achieve the minimum requirements quickly, but to instead do everything possible to overachieve.

The pursuit of high performance means that you try to maximize your success at work, which might mean sacrificing activities outside of work that you enjoy, like spending time with your friends or attending a local gym class. You can slice your time pie any way you like, but a larger slice in one area requires a smaller slice somewhere else.

That sacrifice pays off through a virtuous circle of success. If two equally skilled and motivated people engage in an activity, and one person spends 25 percent more time on it, then, on average, the person who puts in more time will producer greater results. By putting in the additional effort, he or she will learn more and become a better and more capable contributor in the future. As a bonus, that investment may also be recognized in their organization, and as a result, grant that person greater access to new opportunities and senior leaders who can serve as mentors. Success isn't guaranteed, but making the sacrifice makes you more likely to succeed than someone who puts less on the line.

How your performance compares to others also makes a difference.

Let's assume that you and Susie have similar sales territories and identical products to sell, and you hit 125 percent of your goal. Great job! Susie hits 150 percent of her goal. You had a great year, but Susie had a better year—she's a higher performer.

That doesn't mean you should treat coworkers like competitors, but it's important to recognize that your performance is evaluated not just through what you deliver, but in relation to how your peers perform. It doesn't mean that you have to be the best at everything, just remember that someone else is always trying to be the best at anything that you do.

The good news is that high performance isn't mandatory. You can still live a happy, healthy and wonderfully fulfilling life without being a high performer. Still, understanding the high performer mindset can help you create a solid springboard for all your future endeavors.

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