Why do we wear watches on our left wrists?

Q: Why do you wear your watch on your left arm?

Most people are right-handed, but most wear their watches on their left arm. Why do people wear their watches on the opposite arm?

A: To avoid shock, I started wearing it on my non-dominant arm.

　Most people wear their watches on their left arm instead of their right. The reason for wearing a watch on the left arm instead of the right is that most people are right-handed. Wristwatches became popular in the 1910s, and from the 1930s onwards, they began to replace pocket watches. When people started wearing wristwatches, one of the problems they faced was that they were prone to breaking. The balance wheel, which supports the heart of a mechanical watch, is only half to one-third the thickness of a human hair. Therefore, if it was subjected to a shock, it would easily break. It is not surprising that many people began to wear their watches on their non-dominant arm.

　Incidentally, from the late 30s onwards, even inexpensive mechanical watches began to be fitted with a part called a "shock-proof device" to absorb shocks. As a result, wristwatches became suitable for everyday use, but because they were precision machines, they still required careful handling. Some watch manufacturers also make watches for left-handed people. The main difference is that the crown, which sets the time, is located on the left side of the case, rather than the right. The most well-known example is Panerai's so-called "Lefty" model.

　Thanks to advances in watch technology, it's now easier to wear a watch on your dominant wrist without causing any problems, not just with quartz watches, but even with complex mechanical watches. However, strictly speaking, if you wind a mechanical watch designed to be worn on the left wrist on your right hand, the watch's speed will often change. If this happens, it's a good idea to take the watch to a manufacturer or watchmaker for a readjustment.