Compared with manual machine tools, one of the more significant advantages of high precision cnc machine in auto parts manufacturing is processing speed, and the delivery time is particularly short during small batch production. Since machining is automated by the computer, there is no need to factor human constraints such as fatigue into the process.

However, conventional machining may be faster in some cases, such as when only a single unit of an object needs to be produced. In these cases, the time required to create computer instructions can exceed the time required to manually machine individual parts.

Another reason why car manufacturers favor high precision cnc machines is the accuracy and high precision of the craftsmanship. The digitization and autonomy of the process leaves little chance of error, while ultra-high-precision CNC machines can provide tolerances of ±0.001 inches. Understandably, the automotive industry often requires such fine tolerances because failure of an engine or other critical components can have serious consequences for the end user. The production of end-use metal parts often requires precision machining of automotive components, although looser tolerances are available for prototype CNC parts.