Mechanical watches have a mechanism that is moved by power generated as the mainspring unwinds, and small metal parts that work together to control accuracy. The fragile metal parts of a mechanical watch are easily influenced by environmental factors such as temperature, gravity, and shock. Also, conditions of use such as regular usage time, movements of your arm and winding state of the mainspring can influence the gain / loss of the watch.
Temperature : Do not place the watch where the temperature is extremely low / high (less than 5ºC or more than 35ºC)
Mechanical watch parts are metal and slightly expand and contract with changes in temperature, and this influences accuracy. Normally, under high temperatures, a watch tends to lose time, and under low temperatures, it tends to gain time.
Magnetism : Keep the watch away from magnetic fields
Watches can be adversely affected by magnetism and may gain or lose time. It is important not to leave a watch close to magnetic objects for a long time. In particular, cell phones, television and PC speakers, magnetic necklaces, handbag clasps, hair-driers, electric razors, magnetic parts of refrigerators are all magnetic. An affected watch remains magnetically charged even after being removed from the magnetic source.
Shock : Strong shock may affect accuracy
It is recommended that you remove your watch before playing any sport that involves strong impacts. Any direct impact to your wrists can affect the very small parts inside the watch. Dropping the watch may also cause damage.
Position : The accuracy of the watch is affected by its position when it is not worn on the wrist.
The rates of loss / gain of mechanical watches vary slightly depending on positions they are put in, such as being placed horizontally with its face or back turned up, or being laid on its 12:00 / 3:00 / 6:00 / 9:00 side respectively. This is because gravity affects the operation of the inside movement of the watch. Experiment with storing the watch in various positions for 7 to 8 hours when not in use and check the loss / gain of each position. By storing the watch in a resting position that minimizes loss / gain you may counteract the loss/ gain which occurs while the watch is being worn.