I wonder if there's some control-theory reason why one's unsynchronized circadian rhythm is on average slightly longer than a day? Intuitively it seems that one

I wonder if there's some control-theory reason why one's unsynchronized circadian rhythm is on average slightly longer than a day? Intuitively it seems that one might actually have more consistent synchronization with the solar cycle if upward pressure from a natural setpoint is balanced by downward pressure from end-of-day environmental signals (light levels, etc). Or in other words, the body has evolved a slight margin to allow for adjustability "in the field" via feedback loops. But that's just a guess and I can't seem to find anything in a quick search... anyone know more about this?