I ordered my medium Cartier Santos pre-owned from eBay, and I believe it became magnetized during shipping. It was running roughly 15-20 seconds fast per day.

I was excited for the new toy, so I didn’t take the time to let it fully lose energy before pulling the crown and taking it to a watch servicing person to be de-magnetized.

Now, about 2.5 months later, it keeps time as well as my quartz watches. It doesn’t seem to run fast at all any more, and I never have to adjust it unless I stop…

Has anyone ever experienced a watch naturally de-magnetizing over time?