Totally normal. The watch is affected by gravity, temp, humidity, all kinds of other things that vary in your daily life.

You have to remember that what's ultimately happening here is a wheel that weighs fractions of grams is turning back and forth on a spring that weighs basically as much as the air around it. The accuracy of this systems beat rate is what largely determines the accuracy of the watch and you can affect it by blowing on it gently. Big changes, like moving your wrist while playing sports vs a day where you move your arm very little can make a big change to how that system functions.

 

Yes. As to what may cause this, it could be the wearing habits of the wearer, such as having a more sedentary day than other days.

Excellent, thank you.

 

Yes. As to what may cause this, it could be the wearing habits of the wearer, such as having a more sedentary day than other days.

 

Absolutely normal.

 

Totally normal. Precision is more of a thing with mechanicals/automatics, rather than accuracy. Your watch can be comfortably within the specified +/- spd, but it's deviance from zero will vary due to factors others have mentioned

 

Mine drift, but usually not noticeable to me unless I time them for a set period.

All part of the watch game.......

 

ACCURACY AND PRECISION ARE NOT THE SAME THING
However, before we continue, it is worth noting that accuracy and precision are not interchangeable terms. Accuracy is the measurement of deviation from a given reference or target. The less deviation from its reference point, the more accurate something is. So, a watch that loses less than a second a day is more accurate in timekeeping than a watch that loses three seconds a day.

Precision, on the other hand, is variation averaged over time. The less variance there is, the more precise something is. Therefore, a watch that loses four seconds every day may not be accurate, but it is still precise in the amount of time it loses.

5 Most Accurate Watch Movements Ever

Another obsession for many horologists and watch lovers is that of the accuracy and precision of a watch.

www.livwatches.com

 

As others say, this is normal, and that's the fun or sad part of mechanical watches. You feel good when it performs over its spec but your brain starts to think of all sort of reasons when it doesn't.

 

One more factor and reason for deviation can be positional variation due to how the watch is kept while the wearer is not wearing the watch like ( watch kept face up, crown up, crown down etc. ). Also depends on how the watch manufacturer has checked for positional variation ( 3 to 6 positions ) for a particular watch which affects timekeeping. In some cases once you are able to understand this then you can place the watch and keep the timing more or less same ( For eg if you place the watch crown up position the watch speeds up by 5 seconds and if you keep the watch crown down it loses 5 seconds so you can alternately keep it up and down and get 0 seconds time variation )

 

It’s highly unlikely that typical daily variations in your activity, level, temperature, humidity, etc. are great enough to make much of a difference. Most of us are not working on an oil rig in the north Atlantic, where wide variations in temperature and humidity are expected. Most of us are not routing, riding mountain bikes across the desert for a few days and then spending a couple of days in an air-conditioned hotel, sipping daiquiris. So no, I don’t think it’s normal.





-NoSeasBoludo-

 

So no, I don’t think it’s normal.

I think it is.
Even in resting positions it varies. This is half a year's worth of daily measurements, the rate in different positions is represented in a cumulative probability density, the fit is a normal distibution

σ is the standard deviation in s/d, so yes expect some variation from day to day

 

With such tiny deviations I’m sure you would never notice in normal wear, and as others have said normal.

Sudden large deviations, especially a loss, are indicative of movement issues usually.

 

Only if it is one of Seiko’s finely tuned and regulated Factory Watches! Vance.

 

Check it overnight in different positions, i.e resting on crown, face up, face down. You may be able to self regulate. E.g. watch runs 4 seconds fast on the wrist and 2 seconds slow overnight with the crown down then you're tightening the overall error.

 

Deviations such as you describe are perfectly normal.

 

It's normal, and driven by two key things - positional variation, and isochronism.

All watches will have positional variation of some kind, and often even chronometer rated watches (or better) can have fairly large differences in how they run when in a specific position, so as much as 10 or 12 seconds per day difference.

This variation will increase if the state of wind varies, so it can result in fairly significant difference from day to day. Doesn't mean it always will, but it can.