Litre, cm, metre - all are human-size units that are useful. It's easier for me to ad-hoc measure a cable in metres than in feet because the distance between my

Litre, cm, metre - all are human-size units that are useful. It's easier for me to ad-hoc measure a cable in metres than in feet because the distance between my hand and my opposite shoulder across my chest is about 1 metre. Similarly, a kg of sugar weighs about the same as a litre of milk, and I've been drinking milk from litre cartons all my life. (As a kid in Ireland, there were three main sizes in the shops, 1 pint and 1 litre cartons and 2 litre bottles. 1 pint was always too small for a family of three - you'd run out before it went off.) I think you're labouring under parochialism of measurement. Grow up under a different system and you'll see there's nothing special or advantageous about the imperial system at all.