this Bifora watch demonstrates that a watch can remain waterproof for some 77 years with the first set of gaskets:
Notice that there is no corrosion on the dial, even not on a spot where the lacquer was occasionally damaged when removing the hands.
The maker, Bifora/Bidlingmaier started as case maker:
bidfun-db Archive: Watch Movements: Bifora-Uhrenfabrik, Joseph Bidlingmaier, Schw?bisch Gm?nd
And likely therefore he knew that an Oyster needs continuous water exchange to survive, while a movement does not. So they applied a rather thick chrome layer, which not only protects against wear and corrosion, but also gives a smooth and glossy gasket seat. So the lead gasket wasn't damaged by occasional opening and closing the case, and thus still keeps water reliably out.
And even more outstanding: The crown gasket is adjustable by squeezing it with a screw ring, to compensate wear to some extent:
And if a certain limit is exceeded or the material becomes hard, the gasket can be replaced with kitchen equippment, and without need of a new crown.
Regards, Roland Ranfft