Joab drew nigh unto battle against the Syrians He acted very wisely in assaulting the mercenary army first; for they that are hired to fight generally take great care to save themselves, having little regard to the cause for which they fight. Then fled they also They seem not to have struck a stroke, but provided for their safety by retiring into the city, near to which their army was drawn up. So Joab returned Here is no account of the number of the slain, who, probably, were few, because they did not fight, but flee. The year also seems to have been so far spent that it was not a fit season for laying siege to the city. See 2 Samuel 11:1.
Related Commentaries of 2 Samuel 10:13
2 Samuel 10:13-14
13 And Joab drew nigh, and the people that were with him, unto the battle against the Syrians: and they fled before him.
14 And when the children of Ammon saw that the Syrians were fled, then fled they also before Abishai, and entered into the city. So Joab returned from the children of Ammon, and came to Jerusalem.