And YHVH gave Lachish into the hand of Israel, and he captured it on the second day and struck it with the edge of the sword, and every person in it, as he had done to Libnah.
Joshua 10:32

Joshua approached Lachish and Eglon as if preparing for a lengthy siege, but those cities fell quickly. After that, he stopped laying siege to cities because he knew there was no need. "YHWH Elohim of Israel fought for Israel". Joshua 10:32-42