How are people getting team captain roles in sports before their senior year?

Ok this genuinely feels like such a dumb question, but its something that has really been bothering me as I work on apps.

I'm a current senior and have played basketball and track through all of high school. In my experience, all the captains of all the teams I have been on in high school have been seniors. And yet when I'm reading people's stats on this sub or other subs, people list "Team Captain" as part of their ECs, and I'm just completely perplexed as to how they're doing it. And it's not just on Reddit, every damn example essay about leadership on all these different websites has some mention of the applicant serving as a team captain for multiple years. What kind of coach is naming an underclassmen team captain?!

Am I cooked for writing about my experience in sports and not being a team captain? I'm also trying to apply for an ROTC scholarship where being a team captain basically feels like a pre-requisite. Can someone explain how yall are doing it? Because I have a realistic chance of being a captain in both basketball and track this year, but probably won't find out until after applications are due. So basically I have no way of showing a leadership role in athletics on my application.