Einstein did not understand REAL WORLD "loops" just as the Pope did not understand the loop made by Magellan.
The Pope did understand it after a number of people explained it to him,
but Einstein held on to his mis-perception and with the help of a friendly Mass Media brainwashed the masses to believe
that if you would get a day older or younger by looping about the Earth's axis.
"Upon returning the expedition found its date was a day behind, although they had faithfully maintained the ship's log. They lost one day because they traveled west during their circumnavigation of the globe, opposite to Earth's daily rotation. This caused great excitement at the time, and a special delegation was sent to the Pope to explain the oddity to him."