It's all about the place where the mechanical clock was invented, and the movement of the Sun across the sky.
Before the invention of mechanical clocks, people determined time by a sundial, which consisted of a dial and a rod, the shadow of which followed the movement of the Sun across the sky, showing the true solar time. In the Northern Hemisphere, the shadow moves in exactly what we call "clockwise".
The inventors of the first mechanical watches quite logically imitated the movement of the shadow in a sundial. And if this happened in the Southern Hemisphere, then the clockwise direction would be the opposite.
By the way, regarding the Northern and Southern Hemispheres, there is an opinion related to the direction of rotation of the water when draining. It is believed that the moment when the vessel crosses the equator can be determined by the change in twisting to the opposite. This is how the Coriolis effect manifests itself.
Critics of the claim say that in both the Southern and Northern Hemispheres, the sinkhole can spin clockwise and counterclockwise. This is influenced by the geometry of flows in the liquid, the features of the geometry of a particular bath, the structure of its surface, and the configuration of the sewer system.
In practice, the effect only appears in carefully planned experiments carried out far from the equator. They use strictly symmetrical vessels, control of external conditions, and many hours of liquid sludge before measurement.
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