What is the disadvantage of the English system? Please and thank you!!!

The advantage of the metric system is that units differ by a factor of 10 (or 100, or 1000, etc) so it makes it easy to convert from one unit to another simply by moving the decimal point. For the English system, there are 12 inches in a foot, 3 feet in a yard, 5,280 feet in a mile, etc.; therefore, it is NOT easy to convert from one unit to another. Converting 1 km to m I can do in my head as 1,000 m. But converting 18,328 feet into miles means I must divide 18,328 by 5,280 and I need a calculator for that PLUS I must learn the conversion factors.

Oh yeah, I knew that, but I thought there might be more to it. Like maybe a specific disadvantage to the English system that isn't in comparison to the metric. But thanks anyways!