[masto]

The one that really surprised me for some reason was PCB manufacturing. The Strange Parts YouTube channel has a few tours of Chinese factories, and I guess I pictured that it's just some sort of giant clean room with a long conveyor belt that goes through all the processes on its own. So I was not expecting it to start with grabbing a blank PCB from a pile stored outside and taking a band saw to it. Such a mix of high-tech automation and human hands picking things up, racking them on the table, and sticking them into the next machine.

[dfox]

The board level electronics assembly is mostly an solved problem that can be automated perfectly fine, but when you get to through-hole almost nobody does it, because (a) the THT capable pick and place machines are uncummon and thus somewhat expensive (b) it often requires more expensive parts that are compatible with such machines (better geometry tolerances, surfaces for the machine to pick them...) and finally (c) the NRE costs of getting that to work.

That said, then there are niches where the automated THT assembly apparently makes sense and all the NRE costs seem to be offset by lower per-unit costs of the PCB material itself. Prime example is mid-range to high-end home AV equipment (Japanese branded if not made in Japan outright), where the large mostly empty single-sided FR-2 boards with truly ridiculous amounts of obviously machine populated wire-links and discrete THT radial components are particularly striking.