A Community Devoted to the Preservation and Practice of Celestial Navigation and Other Methods of Traditional Wayfinding
From: John Clements
Date: 2020 Oct 27, 10:49 -0700
Based on a detailed years-long study of ... no, actually, I just read the wikipedia page.
It appears that quartz watch accuracy is generally fairly stable, and that the principal factor affecting regularity is temperature. Specifically, the wikipedia page suggests that a change of 10°C could result in a change in the speed of the watch of approximately 110 seconds per year, ballpark 1/3 second per day. Apparently, one solution to this is just to wear it all the time, which will tend to regulate the temperature. Clearly I should stop taking my watch off at night.
Naturally, this is all independent of the manufacturing error/imprecision, which should result in a steady and predictable error.
Disclaimer: I have no idea what I'm talking about. All of this is probably wrong.