Factory standard of mechanical watches: Swiss men's watches: one-day error +-30 seconds, Swiss women's watches: one-day error +-40 seconds, Japanese men's watches: one-day error +-50 seconds, Japanese women's watches: one-month error +- 15 seconds; Mechanical watches rely on internal mechanical devices to control the watch to walk evenly and accurately. These mechanical devices will be affected by gravity, environmental temperature and so on, resulting in errors. Generally, the errors of mechanical watches are calculated by the day, which are different according to the model and manufacturing quality of the movement. Generally, the error within 30 seconds every day is within the normal range.

Some movements with higher precision, such as the Observatory series, can reach about 10 second. Quartz watches use a timely vibrator to replace the balance wheel in mechanical watches, and use its correct high-speed swing to time. Generally speaking, quartz watches have high accuracy. The Swiss standard is that the monthly error is within 15 seconds, and some precision movements can reach the annual error in a few seconds. Generally speaking, it is normal that the daily average error of mechanical watch movement is within +/- 15 to 30 seconds.