The No. 1 trait bosses look for when promoting employees, says ex-CEO and Harvard expert

Sometimes, exceeding your goals and having a great attitude is enough to get a promotion. But often, bosses look for something more subtle, says Harvard Business School executive fellow Bill George.

People who "focus on doing an outstanding job in leading [their] team" are in the "best" position to get promoted, says George, the former head of health care company Medtronic. In other words, CEOs and other leaders may want to see you guiding and inspiring the rest of your team.

Great employees — the ones managers tend to see as worth promoting — don't just boss their co-workers around. They excel at building trust with the people around them, which requires a certain amount of self-awareness to achieve, George says.

"Many people do not know who they are," George wrote in his book, "True North: Emerging Leader Edition," which published in 2022. "They are so focused on trying to impress others that they let the world shape them rather than shaping themselves into the kind of leaders they want to be."

The more self-aware you are, the more "your leadership will be authentic and people will naturally want to associate with you," he added.

Why leadership and self-awareness can help you get a promotion

When you know your strengths and weaknesses, you can use them more effectively in the workplace. Traits like emotional intelligence, adaptability and mindset particularly matter, because they can help you navigate challenges and make a lasting impact on your team, research shows.

You can start cultivating your self-awareness with a three-part exercise, Juliette Han, a Harvard-trained neuroscientist, told CNBC Make It last year:

1. Reflect on your interests and skills, so you can specifically define your strengths and the job responsibilities you'd enjoy. What are you good at? What do you like doing?
2. Ask for feedback from your managers and co-workers. The way they describe you and your work can help you learn a little more about how other people see you.
3. Use all of those takeaways to figure out which skills you want to hone or incorporate more into your work.

"You can have all the technical skills and charisma in the world, but if you're completely oblivious of yourself, how you come across and interact in the world, it's a lot harder to build strong relationships, interact with your boss and co-workers and deepen the friendships you need to truly succeed," Han said.

You may discover that guiding and inspiring others isn't your strongest suit, pushing you to leverage other leadership skills — like critical thinking, decision making or conflict resolution — to be a better candidate for promotion.

How to make your case

Even if you deserve a promotion, you might be roadblocked by other factors like your company's budget. Or, your boss could be totally unaware that you feel ready to move up the ladder.

Try sitting down with your manager and making your case. If they say no, ask them why — and use their response to come back with a stronger argument, or create a plan to meet their expectations, OpenTable CEO Debby Soo told Make It in 2022.

Don't let a "no" keep you from asking again, said Soo: "Oftentimes, a no isn't a hard no, it's a 'not yet' or 'no, but how about this?'"

If you work to meet their expectations, ask your boss again and they still don't seem to understand or appreciate what you bring to the table, it may be time to look for new opportunities elsewhere, she added.

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