Where does the text state the true frontier of innovation and most specialized roles lie within Additive Manufacturing?

Answer

Within the materials that make these processes possible.

The text explicitly states that while machine operation and design are essential, the most specialized roles and the true frontier of innovation reside in the materials that enable additive fabrication processes.

Where does the text state the true frontier of innovation and most specialized roles lie within Additive Manufacturing?
technologyRoleMaterialmanufactureAdditive manufacturing