I am 5ft 9 inches tall, I weigh 12 stone, I live 2 miles from the nearest town and my car does mpg.
I have no idea how tall I am in Metric, how much I weigh, how far it is or how many litre you would need to travel a mile or what ever complicated calculation the foreigners use.
I go into the Butcher and ask for a pound of mince or a 9 ounce steak, Eggs still come in half dozens.
I was watching something the other night on TV. Apparently the French tried to metricise time. There are still samples of these metric clocks.
I have to admit small measurements are easier in metric, I know how big 5mm is but I have no idea what 3/16 of an inch is.