Years ago, I hired my ideal candidate for a management role.

• He was the top performer by far on his team.

• He was eminently likable and charismatic.

• He had expressed a desire to move into leadership.

No one knew the work better than him, no one was more liked by the team, and he was hungry for the role. I could not have found a better fit.

Fast forward just a few months, and we were moving him out of the role.

My top performer — the ideal candidate for the role — had washed out in record time, and it was entirely my fault. Even with decades of leadership experience, I still misunderstood one fundamental piece of leadership.

What We All Get Wrong About Leadership

When I interviewed applicants — especially ones early in their careers — I used to ask them, “Where would you like to be in the next five years?”

Depending on their bravery, I usually heard responses like this:

• “I’d like to have grown into a position of leadership.”

• “I see myself growing to eventually run my own team.”

• “I’d like your job.”

That last one is my favorite. I used to always think, “You don’t know anything about my job.” Back then, I didn’t fully understand my job either.

We tend to see leadership as the natural progression of a successful career. It’s something you get promoted into. You begin as a bright-eyed, entry level hire, and you outperform everyone else, climbing the ladder until you’re promoted to a leadership position.

That’s how I thought about leadership when I hired my “ideal candidate,” and that’s how he thought about it as well.

There are skills and traits you must have to be the top performer on a team, and there are skills and traits you must have to lead a team — and while they overlap in some areas, they are different and distinct skill sets.

More specifically, there is one skill a leader must have — the most important skill a leader can have, in fact — that not all top performers have.

Great Leaders Make People Better

My ideal candidate was a talented, hard working, likable guy. If you gave him an assignment, he would knock it out of the park.

But he had never once been responsible for someone else’s growth — and if you truly distill leadership down, that’s it.

The one skill a great leader can’t live without is the ability to develop their employees. If the people you are responsible for aren’t growing, your team is stagnating, which means no one is getting what they want:

• Your top employees aren’t getting the chance to develop, making it much more likely they’ll be recruited away.

• Your struggling employees aren’t getting the chance to improve, making it much more likely they will fail.

• Your leaders — the people who hired you for this role — aren’t seeing the results they are looking for, making it much more likely that you won’t grow (or worse, you won’t last).

A lot of the people who find their way into leadership and succeed have this skill naturally. They may not even know it’s a skill, they just do it. When they hire new managers, they make the same mistake I made. They assume everyone can “just do it.”

When I hired my top performer, I gave him no real leadership training, no simulation — I thought he was so good that he’d hit the ground running.

That was unfair to him. He was every bit as good as I thought he was, just not at leadership, and none of us had the awareness to teach it to him.

In hindsight, we set him up to fail from the start.

If I could go back and give him one piece of advice, it would be this.

How To Get Better At Employee Development

Find the leader in your company who clearly loves developing people, who inspires their employees. If you’re having trouble, just ask your peers who their favorite leader is.

Once you have your leader picked, mirror them.

When I have the chance to give young professionals advice, I always stress the importance of mirroring versus mentoring. A mentor is incredibly important to have, but you can’t always get the best leader in your company as a mentor. You can always, however, mirror them.

Take note of how they interact with their employees:

• How do they evaluate strengths and weakness? Are they accurate?

• How do they give feedback?

• How do they make themselves available for interactions?

• How do they motivate their team members?

Compare those traits to your own. What areas do you need to improve in? What habits and tactics can you mirror from them? This is your chance to practice before the role becomes real.

Once you start consciously incorporating their behavior into your life, you’ll be amazed at how quickly you improve your employee development skills. When and if you decide to move into a leadership role, you’ll be prepared.