Do not swallow bait offered by the enemy. Do not interfere with an army that is returning home.
Deceit is a common in strategy and tactics. Watch for things that seem easy, for they may easily be a dangled bait, designed to catch the unwary with a hidden hook that will snag and prevent escape.
Also, if an army is in final retreat back to its homeland, then pursuing it may result in more loss than gain. If you can win the war by ceasing hostilities now, why waste lives further? It is a basic principle of maneuvering to win without fighting.
There may be good reason for pursuing a retreating army, for example if they are retreating only to regroup or re-arm.
Deception is also common in business and a easily provoked competitor is one who may be easily defeated.