Over the course of my cardiac surgery residency, I have come back to the same role several times.

For instance, I have worked in the cardiac surgery intensive care unit as a covering provider in my first, second, fourth and fifth years of training.

And what is always remarkable to me is just how different I am as a provider each time I come back to the same role. My understanding of physiology continues to evolve, and I become more comfortable making complex decisions. I can think of more ways to help patients recover more safely and quickly.

It is not a matter of effort, but rather of experience. Each time I was in that role previously, I was doing my utmost, doing my best with what I knew at the time. Similar to looking at yourself in the mirror each day and then seeing photos taken years apart, it is hard to tell how you’re growing in the moment, but the change is obvious when you look back.

Knowing this about myself, now I recognize just how tremendously important experience is in any operation. Experience can make everyone on the team more effective. Experience can raise the standard of care. Only time and work can build experience.

As the pandemic has worn on, health care lost and continues to lose providers, often among the most experienced members on the team. Burned out and fed up, some are changing fields, others are retiring earlier than they’d planned.

Even filling their positions cannot make up for the collective experience we have lost, and the time and energy it will take to restore it.

We should be talking more about this as a serious issue. It will affect our society for the years to come.

Whatever I do in the future, I will do whatever is within my capacity to value and retain human capital, above all else.

Individually, we get to have blind spots and occasionally make mistakes because, as a team, we are looking out for each other. Our collective experiences provide a safety net that can’t be easily mended once torn.

When an experienced nurse or doctor leaves, we might talk about a vacancy to fill. But what if we instead considered how many emergencies they helped oversee? How many trainees they taught, and how many families they comforted?

The most important part of any operation is the people. Protecting and retaining health-care workers, especially those already established in practice, should be a national priority. Their loss may not be obvious on balance sheets, but it will be felt.

Jason Han is a cardiac surgery resident at a Philadelphia hospital and contributor to The Inquirer’s Health section.