What does accuracy mean?
Accuracy describes how much a watch deviates from the exact time within a certain period.
For mechanical watches, the deviation is often given per day. Small daily deviations are normal for automatic watches.
Quartz watches generally run much more accurately, as they're controlled electronically. Mechanical movements react more strongly to outside influences.
Accuracy can be affected by, for example:
- Temperature
- Position of the watch
- How it's worn
- Power reserve
- Magnetic fields or shocks
If the deviation is noticeably greater than usual, it may be worth having the watch checked or regulated.