Well, you see it all started when Chinese parents, especially fathers believes that hitting a child, or spanking a child, is a good way of instilling discipline on them. Since leather belts are not used in the olden times, they would normally use stick or brooms.
Grandparents, especially, grandmothers and mothers will normally stop their husband from hitting their children because they know being hit with a broom is really painful. But since they cannot openly contradict the patriarch of the family, they would have to think of creative ways of stopping their husbands from using the broom. So they have to be creative in trying to stop their husband from using the broom, and since most Chinese believes in Feng Shui, they would often say that hitting somebody with a broom would bring bad luck to the hitter. This little white lie will often save their children from being hit by the broom.
As most often, these things get accepted as fact and becomes a regular belief. But there it goes, another myth busted!
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