The phrase milk run originated in World War II, when US Army Air Corps and RAF aircrews used it to describe any mission where minimal resistance from the enemy was expected.
Video Milk run
History
In American culture, a milk run was literally the distribution of milk bottles by the milkman. On his daily route, the milkman simultaneously distributed the full bottles and collected the empty bottles from a previous delivery. After the completion of round trip, he returned with the empty bottles back to the starting point.
In the context of logistics, according to Winfrid Meusel, milk runs were any routes that originated by identifying potential circular tours, whereby the utilization of trucks could be increased and logistics costs could be reduced.
Maps Milk run
Airline routes
In the commercial airline industry, "milk run" has been used to describe multi-stop, regularly-scheduled flights performed by a single aircraft. Two examples of such routes were the Alaska Airlines Milk Run, serving cities from southeast Alaska to Seattle, and the Regional Express (Rex) Milk Run in Queensland, Australia.
References
Source of the article : Wikipedia