I still haven’t forgotten that day, but not for the reasons you might expect.

We sat down at a table and I began telling this busy man what I was learning in my graduate program and in the store and what I hoped to contribute at the corporate level. He was interested and engaged, but not enough to miss the young mother who had walked past my line of sight and into his with a stroller, her items and a small child in tow and was approaching the door. He quickly jumped up from the table, held the door open for the customer and then returned to our table where I continued my spiel.

And then it happened a second time.

Talk about making a poor first and second impression. But it gets worse.

I had somehow failed to let my operator know the director would be stopping by his store. He had taken the Friday afternoon off to celebrate his son’s birthday at the lake over the weekend. He was also in the process of applying for a larger store. So when he found out the director would be coming by, he had to make a mad dash from his family at the lake to get back to the store in time to greet the director and make a positive impression.

Here’s the ironic part: both my operator and the director had gone out of their way to put their focus on me – to help me win. Unfortunately my complete tunnel vision on my own goals blinded me to the situation and I missed my most important objectives: to serve my customers and my operator. I cared about them, but in the moment I was focused only on me. What a mistake!

In his new book The Heart of Leadership, author Mark Miller says the one distinction that sets great leaders apart is this: Are you a serving leader or a self-serving leader? He then goes on to talk about the character side of leadership, which starts when we think others first. It’s a mindset more than anything else. Instead of being in the leadership game solely to accomplish personal victories, the greatest leaders use their influence and resources to help the people around them be more successful. It’s not easy, but it is crucial. Without leadership character, a person may attain a position of leadership but is not likely to keep it for the long-haul.

If this had happened in a military context (I was in the Army Reserves at the time), I would have been dressed down so severely I might not have talked to a superior ever again. But my operator never mentioned it to me and is still a champion of my goals today. Years later, the director is now a senior director. My operator got the bigger store and is currently being considered for a second one. I never did make it into the corporate office and became a consultant instead. I’d like to think things have worked out for the best.

I missed an opportunity in the store that day, but hopefully I haven’t missed out on the greater lesson: to use who I am and what I can do to help those around me win. Will you join me?

Nathan Magnuson is a leadership consultant, coach, trainer and thought leader.  Receive his new ebook Trusted Leadership Advisor by subscribing to his website  or follow him on Twitter.