I've worked with the factory techs before, and my experience was the same. The techs move assemblies from point A to point B, and hit the big green go button, a

I've worked with the factory techs before, and my experience was the same. The techs move assemblies from point A to point B, and hit the big green go button, and occasionally hit the big red stop button. They know how to diagnose failures that they've been given a runbook for. New failures they're clueless about and don't have even the first idea how to diagnose. For that, there's the engineers that designed the station and the engineers that designed the underlying thing being assembled. Once the factory is up and running, the engagement of the engineers follows a power law distribution until the failure rate is below whatever is considered acceptable for what you're producing (starting point: 0.1%), at which point the engineers are fully disengaged and fully working on the next product. Factories do not need engineers on staff other than for reconfiguring space to support producing a new widget and controlling the data flow from stations to whatever central repository exists within the factory confines.