This is true of basically every army on Earth, because it works. In fact, the USSR notably attempted to do away with the idea of an officer class in the Red Arm

This is true of basically every army on Earth, because it works. In fact, the USSR notably attempted to do away with the idea of an officer class in the Red Army (since it was seen as un-Socialist) and wound up changing their mind and re-instituting officers about a decade later.