Final answer:
Machine safeguards must protect the operator, machine, environment, and materials being processed.
Step-by-step explanation:
Machine safeguards serve to protect not only the operator, but also the machine, the environment, and the materials being processed. It is essential to safeguard all these elements to ensure safe and efficient operation. For example, protective barriers and enclosures can prevent operators from coming into contact with dangerous moving parts, while also protecting the machine from damage caused by external factors. Similarly, safety measures can be implemented to prevent the release of hazardous substances into the environment or to control the temperature and pressure of materials to avoid accidents or damage.