Why does my left AirPod die before the right?

I have second generation AirPods and I have an issue where the left dies before the right. It’s all of the time regardless of which one I put in my ear first, and the right is always still half way charged after the left dies. When I put the AirPod back into the case with the other, a few minutes later it’s the same battery percentage as the right. And yes, my microphone is set to automatic but I’m not sure if this is the case of why it dies before the right. I’ve also tried draining both to have them charge at the same time and the left still dies way faster.