Measuring Differences

Resetting my clock today, it occurred to me that most measures such as distance, weight, volume, etc. vary by country or region, but one measure, time, doesn't. The 24 hour clock is present everywhere I can think of. There are variations, e.g. Daylight Savings differs across both countries and regions in the U.S., and the words differ, but no the clock. Why?

Global coordination of the clock must be far more important the global coordination of other measures.