I was just explaining this to Mrs. Thinking a couple days ago. The advantage of a highly composite number (composite being the opposite of prime) is that you can evenly divide it many different ways. You can evenly divide a 12-inch foot into 2, 3, 4, 6 or 12 pieces without getting into fractional inches. Something in base 10, like a centimeter, you can divide by 2, 5 or 10 and you’re done. Thus 12 inches, 60 minute hours, 24 hour days, etc. Some researchers even claim that the absolute size of Imperial units like inches feet, pounds and so on, are more intuitive for humans. No idea if that one is true or not.
well, Looking at my hand palm side up, I can measure exactly one inch from the tip of my index finger to the first crease of the joint.
That works for me.