Many machine tool manufacturers are no longer in business, and this creates a serious problem when spare and/or repair parts must be obtained. Part drawings must be created from samples of parts that are often worn and/or damaged and a person with a knowledge of wear characteristics is necessary.
Practically no one uses paper drawing files any more, as electronic drawings have been the norm for many years, and not every firm wants to invest in the software and manpower to convert paper drawings to the electronic format.
While all machine shops manufacture precision items, not all machine shops are qualified for certain types of manufacturing, especially the production of precision gears and sensitive rotating parts.
And finally, not every firm has a staff engineer who has the time and resources to develop the ideas from concept to working drawings.
I work with many in-State and out-of-State shops and can certainly make recommendations pertaining to the machining services needed.