It turns out, that isn't worth much. Because they upended the factories and sent them to Mexico and China overnight without a person to point and say where the jig was. Seemingly, they figured it out.
To be clear, I'm not actually disagreeing with your point, I do think it's important to have those people. But companies felt otherwise.
At least in the instances I've been aware of, they usually weren't really "overnight". Usually a good bit of knowledge transfer or actually moving institutional people, sometimes having the other factory coming online in parallel so they can tweak processes, etc. Usually a years-long process. I think few truly overnight shut down one factory and opened the other with those other people having zero knowledge or training on specific processes without experiencing big issues.
To be clear, I'm not actually disagreeing with your point, I do think it's important to have those people. But companies felt otherwise.