In theory, a machine can never be 100% efficient due to various factors such as friction, heat loss, and resistance in the materials used. These factors will always result in some energy being wasted or lost during the operation of the machine, preventing it from achieving perfect efficiency. Additionally, the laws of thermodynamics dictate that no process can be 100% efficient as some energy will always be lost to the surroundings in the form of heat. Therefore, while engineers strive to design machines with high efficiency, it is practically impossible for a machine to be 100% efficient in the real world.
