When we tell people to do their jobs, we get workers. When we trust people to get the job done, we get leaders.

To become a leader, we have to go through a transition. Some go through it quickly. Some go through it slowly. And, unfortunately, some never go through it at all.

When we are junior, our only job is to be good at our job. When we’re junior, our companies will give us lots of training—how to use the software, how to sell, how to make a presentation—so that we will be good at our job. Some even get advanced degrees so they can be even better at their job— accountants or engineers, for example. And if we are good at our job, the company will promote us. And if we are really good at our job, eventually we get promoted to a position where we become responsible for the people who do the job we used to do. But very few companies teach us how to do that. Very few companies teach us how to lead. That’s like putting someone at a machine and demanding results without showing them how the machine works.

That’s why we get managers and not leaders inside companies. Because the person who got promoted really does know how to do our job better than we do . . . that’s what got them promoted in the first place. Of course they are going to tell us how we “should” do things. They manage us because no one taught them how to lead us.

This is one of the hardest lessons to learn when we get promoted to a position of leadership—that we are no longer responsible for doing the job, we are now responsible for the people who do the job. There isn’t a CEO on the planet who is responsible for the customer. CEOs are responsible for the people who are responsible for the customer. Get that right, and everybody wins—employees and customers.

Leadership is hard work. Not the hard work of doing the job—it’s the hard work of learning to let go. It’s the hard work of training people, coaching people, believing in people and trusting people. Leadership is a human activity. And, unlike the job, leadership lasts beyond whatever happens during the workday.

Excerpted from Together is Better: A Little Book of Inspiration, in agreement with Portfolio, an imprint of Penguin Publishing Group, a division of Penguin Random House LLC. Copyright © 2016 by Simon Sinek Partners, LLC.