You should visit this museum :
https://www.patek.com/en/company/patek-philippe-museum/the-m...
Since mechanical watches are, by design, open source, there will always be a technician interested in keeping them going.
Since mechanical watches are, by design, open source, there will always be a technician interested in keeping them going.
Even if you have a watch in front of you, it does not mean you can create a copy of it without a lot of work - you need to measure every gear, guess the materials used (how stiff should this spring be?), and re-draw mainplate and dial.
Compare to things like old electronics, which came with full schematics, service manual and sometimes even debugging guide.