I don’t know what set of QC steps are taken by every manufacturer. But I do know that Lange takes the extra step of assembling each of their movements twice. Even then, they admit that perfection is unattainable. It’s merely a goal.
I suppose the takeaway here is that achieving precision is a monumental challenge when you’re dealing with such tiny, handmade machines. But that’s also what’s so compelling to me. Something so small, composed of hundreds of parts, that we make vulnerable by wearing them on our wrists daily. It’s good to occasionally pause to appreciate the artistic and engineering efforts that go into our watches. It’s very impressive that they generally tend to work amazingly well.
An as an aside, with a nod to AP, one of my grails is neo-vintage steel 14802 with salmon dial.