Looking down on the problem
If we look down on Derek’s problem from
outside, we can see that each day, Derek will respond to around 40 e‑mails. On some days, it may be 30 and on some 50, but Derek’s average
is around 40. We know that the average number of e‑mails he
responds to remains stable because the number of e-mails in his in-box never diminishes to 0 or
increases to 100. His 40 per day maintains his
in-box.
On
Wednesday, some of those e‑mails he responds to are from Monday and
Tuesday, but the average remains at 40 per day. “I’m never going to be able to empty my in-box,” he laments.
