For sure, you have heard one of the sayings that women have to wear the watch on the right hand, while men on the left one. In fact, the reason is hidden in the history of the watch.
While first portable watches were invented, they were absolutely different from the current ones, since they came with chains and nobody wore them on the wrist but in the pocket. Meanwhile, when the watches for women appeared they were designed for wearing on wrists only, and women wore them on their right hands.
As for pocket watches, they required careful storage since their mechanisms were too fragile and they tended to break quite often. That is why, once the wristwatches for men appeared, users were afraid of breaking the timepieces and they started to wear them on a non-dominant hand since it doesn’t move a lot as the dominant does.
That is why, if you are left-handed you need to wear your watch on your right hand, and vice versa. However, this rule doesn’t apply to the cases to the timepieces with electronics and modern mechanisms since they are not apt to off.