The requirement for continuous power supply in actuators for load holding depends on the specific actuator and its application. Key considerations include the desired fail condition during power loss or system failure. For critical systems, such as valves in a reactor, the gas valve should fail closed to prevent overheating, while the cooling water valve should fail open to maintain safety. This highlights the importance of designing actuators based on their operational context and safety implications. Ultimately, the decision should align with the specific needs of the system being controlled.