I wore it 24 hours a day, never took it off even to shower. Snorkeled with it too.
When I bought it in Geneva in 1970, there were choices, more expensive choices. I was backpacking through Europe, and could only afford the non-chronometer Submariner, no date.
It kept decent time, but certainly not a second a day. Any $2 street vender Chinese quartz watch keeps much better time.
Going long periods without servicing it no doubt did not help the accuracy. By the time I gave it to my son, it was losing at least a minute a day.
He won't tell me what he paid to have it serviced and restored, but I'm sure it was many, many times the $128 I paid for it new.
Part of the restoration included polishing the case and bracelet, and replacing the crystal.
The sad thing is, because of it's current condition, looks new, and the current value, he only uses it as a dress up accessory. I keep telling him it's an everyday watch, and meant to be worn, but he sees it differently. Maybe I would too if I knew what he'd spent on it.
In the '70's, I was working in NYC, and Rolex on 5th Ave. would adjust the timing, and fix your bracelet for free while you waited. Those days are long over.