(Not in the US.) My partner worked a factory job for many years. They used to have a "specials" group (unofficial name for them), who would be taken on and they would be trained to do just one job, but they would learn it and perform it to a very high standard, day in and day out for many years. They would become very fast at it, and were paid quite well with regard to the average wage in the area.

Unfortunately, they were also the first laid off when automation was installed, and afterwards they were competing for few jobs at the same (regional) low wages with "normal" people.