My dad knew a mail carrier. Tall, lanky, energetic, and a bit of an odd duck. When he started a new route, he'd go through it quickly, finishing early. An early finish meant they'd add more to the route. He'd take that as a challenge, working even harder to get through it early. They'd extend the route again, creating another challenge.

This would repeat until he was nearly running to get the route done in time. At this point things got boring, so he'd use his seniority to switch to a new route. That mean some poor low-seniority sucker would get assigned his very demanding route and struggle desperately with it, finishing very late.

My point being that some people like being heroes, at least for a while. It seems to me kinda like the way I like running races: fun as an occasional challenge partly because doing something unsustainable causes me to push myself.