I heard a story once about a lance corporal who failed to salute a lieutenant. Deeply offended by this breach of military courtesy, the lieutenant directed the young Marine to salute 100 times by way of remedial training.
A Marine colonel happened upon this scene and asked what was going on. He listened patiently to the lieutenants explanation before commenting.
“Lieutenant, you realize that if this Marine just rendered you 100 hundred salutes then you owe him 100 in return.”
The colonel left the scene, the lieutenant now returning 100 salutes as military courtesy demanded.