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@j_bertolotti @geoffl - The French had the right attitude but they couldn't make it stick: "The French Republican calendar time system used in France from 1794 to 1800, during the French Revolution, divided the day into 10 decimal hours, each decimal hour into 100 decimal minutes and each decimal minute into 100 decimal seconds (100000 decimal seconds per day)."

https://en.wikipedia.org/wiki/Decimal_time

Decimal angles too:

"But a second proposal suggested changes went further still. On 1 November 1795 (11 brumaire by the new calendar) a law was passed which required the creation of clocks with ten hours in the day, 100 minutes in an hour, and 100 seconds in a minute. A metric system of angles was also brought in, with 400 degrees in a full turn (100 degrees in a right angle). Now the earth would rotate 40 degrees in an hour and, since the metre had been designed so that one quarter meridian was 10 million metres, each degree of latitude would be 100 kilometres long. It was certainly a rational system but its introduction would require all watches, all clocks, all trigonometric tables, all charts etc. to be changed. Condorcet proposed that teams of out of work wig makers should be used to recalculate new mathematical tables with the new units. Why, one might ask, were the wig makers out of work? Well they had been employed by the aristocrats who, following the Revolution, no longer required their services!

Laplace was enthusiastic and had his watch converted to the new time. His great five volume work Traité de Mécanique Céleste, the first two volumes of which appeared in 1799, was written using the new units of time and angle."

https://mathshistory.st-andrews.ac.uk/HistTopics/Decimal_time/

(Having lost their heads, aristocrats no longer needed wigs.)