The manufacturer suggests that you take the timing of your watch as a function of its daily deviance over the course of a week. rather than taking the deviance for any given day. Most Orient Watch calibers are rated at +25 / -15 seconds per day.
A mechanical watch should not gain more than 2.9 minutes or lose more than 1.75 minutes over the span of a week.
To improve the accuracy of a mechanical watch, it is recommended that you wind up the mainspring every day.
A fully wound mainspring can stabilize accuracy. If the watch is not fully wound the external factors outlined below can more easily affect your watch.
We recommend wearing the watch for at least 8 hours to fully wind the watch, alternatively 30 full revolutions of the crown should fully wind most of our movements if your watch also features hand-winding.
Here are a few factors that can affect the daily deviance your watch may experience.
Temperature:
Typically, temperatures outside the range of 41 and 95 degrees Fahrenheit will have effects on your timing.
The metal parts of the movement can slightly expand and contract with changes in temperature which will influence accuracy. Generally, high temperatures tend to cause loss in time, whereas lower temperatures cause gains in time.
Magnetism:
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. Most household electronics, such as cell phones, television and PC speakers and laptops have magnets in them which can possibly magnetize your watch.
Shock:
Subjecting your watch to shocks and vibrations may impact your timing. We would suggest removing your watch prior to any high-impact sports, such as tennis or when using machinery that may vibrate, drills motorcycles etc... The impact from dropping your watch may also cause timing issues
Position:
Daily accuracy can be gained or lost depending on the way the watch is stored when it is not on your wrist, for example; your watch will have slightly varying accuracies depending on whether its placed on its 12:00 side facing down, vs the 3:00 side, vs the 6:00 side vs the 9:00 side. We would suggest experimenting with storing the watch in various positions overnight in use and check the gain/loss of each variation. If you can figure out which side gains or loses the least amount of time you can offset the gains or less you may accumulate throughout the day.