How "off" can your watch's time reporting be before you feel obliged to correct it? I don't mind a variance of a couple minutes or so, but five minutes' variance is about the limit before I feel I should adjust it. Most of my watches have, quartz, ETA or in-house movements inside. The consequence of that is that I've been accustomed to my watches reporting the right time -- within a minute or two -- for weeks on end. FWIW, over the past 20+ years, the Constellation, an Air King, a Tag Series 2000, and a variety of quartz watches are the ones that have served as my daily wearers, although it's been the Constellation for the past decade or so.
I recently bought my first watch having a Citizen mechanical movement in it and it's been observed as losing about 20 seconds per day when worn daily. Now, I have to say that took me aback; I really expected here in 2014 that that Miyota would perform much more closely to what I've observed from my ETA movements -- 4-10 seconds/day -- the majority of which are ETA-top non-chronometer grade. Boy was I surprised to find that just isn't the case.
I also have a non-descript watch that I bought from a street peddler in Shenzhen. It too seems to be more accurate than is that Miyota movement, and I don't actually have the first idea what's inside that watch. It came only with a "thank you" from the guy who was selling them off a stick from which they were dangling and I picked one. The one I chose, nor any of others, had so much as a cling-wrap-like protective covering on it. Nonetheless, it's holding it's own with my ETAs. (I wore this watch every day for about a month when I first got it, but now, I wear it only when I go clubbing/bar hopping with colleagues at night in Shenzhen.)
My daily wearer is an old Constellation chronometer, but I don't expect watches lacking that certification, or it's equivalent from other countries, to match it. I do expect -- especially in light of that cheap Chinese watch I bought -- to come close, closer than 20 seconds/day. So, am I being unreasonable? Have I just been lucky? Admittedly, if I don't wear a watch every day, I won't notice how accurate it is or isn't and I don't actually bother to check on watches I don't wear daily.
FWIW, the watch having the Miyota movement isn't a daily wear watch for me either, so in the long run, it's accuracy over long periods is a moot point. I just bothered to check since I took the time to write a review of it.
All the best.