Time measurements like heat, mass, length etc are arbitrary units. It is just that they are the oldest.
The Sumerians gave us our time standards and they loved base 12. So twelve hours in the day and 60 (5x12) minutes in the hour. Also 12 months in a year and 360 degrees in a circle.
The French actually tried to implement decimal time after the revolution but reverted back after 6 years or so.
This article suggests 60/60 came from the Sumerians who used a base-12 counting system. This and other articles note that 60 is more flexible than 100 in many ways as it’s divisible by 2, 3, 4, 5, and 6.
The Babylonians invented the 360 degree circle, and so understood the sun to move about 1 degree per day.
The number of days in a week and weeks in a month is based on lunar phases (month=moon, and in Chinese the word for month is the same as moon, 月). This article says the approximately 28 day month is traced to ancient Mesopotamia with leap days used to stay consistent in the long run. As for days of the week that article also says they were based on the 7 non-fixed heavenly bodies visible to the naked eye.
12 hours in half a day is fine for me. 12 can be divided into halves, thirds, quarters and sixths. That's useful for planning out a day. Time is one of the applications where I don't have a complaint about using base 12.
And when you are studying financial mathematics, there 30 days months all around, or not actually each day is counted, or wait it's only work days. For the year you can have 360 days at year, or 365 or sometimes 366. And you need to remember all that shit for tbe exams and never use it again because is the problem for the programmers to solve.
Well, the time for eath rotation isnt a constant, it will slowly decelerate and days will be longer.
Using multiples of 10 for time was considered, but was a shitty option compared to the current deal. Months should all be 30 days and then have a free week at the end of the year tho, egyptian style.
they were, in ancient egypt. They were supposed to be dangerous days, because religion wanted to keep control of the people on the days they werent tied to the regular schedule, by scaring them.
Calendar used in DPRK, basically normal gregorian but the dates are counted from 1912 as Juche era, in a combination of european system and partially Korean system.