To truly become a well-rounded person, you have to embrace all personalities, especially those different from yours. When you do that – when you lean into and rise to the occasion – no job is too big.

In 2004, I was asked to be CEO of J.P. Morgan’s Private Bank, but with a footnote – I would have a co-head helping me run the infrastructure aspects of the business. It was a huge opportunity, but I couldn’t help but wonder if I was prepared for the responsibility that came with managing a 10,000-person organization. And how would this co-head thing work?

After a couple of months in the job, I started questioning the situation. Why wasn’t I asked to do the job on my own? Was I lacking in certain areas? Was it because I was a woman and just had my second child?

I also started having doubts about my co-head: I was a portfolio manager and he was an operations specialist. Needless to say, we had very different visions for how to run the organization. I was convinced we weren’t the right “fit.”

As a result, we simply coexisted, interacting only when it was required. Fortunately, after watching our interactions, the head of Human Resources finally came into my office and told me to snap out of it. She asked me to flip the situation around and use it as a learning experience, and left me with one task: Make it my mission to connect with him personally and professionally.

So I did. I moved into the office next door. I checked in with him first thing in the morning and before I went home. I began attending his operational meetings, sitting in the back just learning and listening. But, soon I was sitting at the table, asking questions, and even making suggestions.

Over time, our morning and evening rituals were longer and more casual. I even mustered up the courage to ask him to grab a beer on his way to the train so we could talk about family, kids and weekend time.

I spent my spare time learning about everything from cyber security to six sigma processing. He began attending my morning markets calls. We were polar opposites, but it had become clear why we had been paired together.

Sure, we still had our differences, but we grew to respect each other.

Shortly thereafter, I became sole CEO and he moved on to run operations for a huge part of the company. I am forever grateful to this man for the hours he spent coaching and teaching me the areas where I needed it most. I can now lead a 20,000-person organization with confidence in my ability to understand the technical and operational side of the business. I’m also grateful my bosses had the foresight to pair me up with exactly the “right” partner.

I learned that being uncomfortable can be a good thing. It gives you the courage to ask the “dumb” question and challenge yourself every day. To truly become a well-rounded person, you have to embrace all personalities, especially those different from yours. When you do that – when you lean into and rise to the occasion – no job is too big.