Abandoned Robots

Abandoned Robots series is a personal IP I created years ago, inspired by the science fiction novel, I, robot, written by Isaac Asimov. It's a post-apocalyptic world where lives survivors of robots from the nuclear war. After the war , mankind is almost extinct on the earth , left the robots there without order and rule. Then, what's the meaning for the robots to keep working ? what will they do after being free from the human's rule?