Windows is always full of surprises. This evening I was copying a large group of files (>50GB) and the little progress pop-up caught my eye about a quarter of an hour (and a quarter of the way done) with its cheerful little message that it would take at least another day to complete its little task. 1/4 done in 15 minutes and the estimate was for more than 25 hours more. At first I pondered the possibility that the programmer was a near relative to an orangutan of my acquaintance. Then that the poor fella was constantly surprised by mathematics. Then I realized the truth. It was intentional.