If I have so much work that I am drowning and people are looking for me to do more and more and more.....
that means my manager failed their Real Time Strategy Game and they need another worker at my level. Maybe that's because the next manager up failed their game, etc etc.
But it doesn't matter why.
I do 9-5. And I go home. That is the employment contract. That is what I do.
I try to make good on my 9-5 so my own self worth is fine. But I only do my job.