Speaking as a long-term collector of mechanicals, I dunno how true a lot of this is for the broad market. First, an ENORMOUS chunk of the middle-high end are w

Speaking as a long-term collector of mechanicals, I dunno how true a lot of this is for the broad market. First, an ENORMOUS chunk of the middle-high end are watches with ETA (or other well-understood mass market) movements in them, and not just models from the Swatch Group[1]. Any reasonable-sized city has a watchmaker who can repair one of those. Sure, if you bought a super-fancy watch festooned with complications for tens of thousands of dollars, you probably need to go to a dealer who may ship it back to Switzerland, but that's the exception. Second, even the in-house movements used by some makes (Rolex especially) are well-understood by non-dealer/non-manufacturer watchmakers. The mainspring on my 1977 Rolex broke a couple years ago; a local fellow I trust replaced it for $200, and that included a thorough cleaning. [1]: The Swatch Group owns ETA, who make movements, but also LOTS of watch brands you know, like Omega, Breguet, Blancpain, Longines, Hamilton, Tissot, and others. My "Bond" Seamaster has an ETA movement in it, for example. The tl;dr is that for most watches, you don't really need "factory" parts for repair.