Comment by nickevante

This is the exact mental model I was looking for.

It reminds me of Kingman's Formula in queueing theory: As server utilization approaches 100%, the wait time approaches infinity.

We intuitively understand this for servers (you never run a CPU at 99% if you want responsiveness), yet for some reason, we decided that a human brain—which is infinitely more complex—should run at 99% capacity and still be expected to handle urgent interruptions without crashing.