21 day delivery in mail order WAS the standard in the late 1940's and '50's. with the truck system. It has no place in a modern world. I spent 36 years pre-retirement in the computer service sector where next day delivery was usually much too slow, and I frequently chartered airplanes to deliver parts in a matter of hours when next flight out with the major aIr carriers would NOT meet customer contract terms. In my world, a week has always been an ETERNITY! Until the trump era post office appointments , even usps delivered in 2 or three days to most of the USA after origin surrender and almost always made 7 day delivery, even with parcel post! FedEx is/was about 72 hours via ground, and UPS about 4 days post tendered. Not at all unreasonable. 10 days was guaranteed and achieved by PonyExpress in 1861 from St Joseph, Mo to Sacramento, Ca about 2100 miles on horseback.
