Waiting for the rabbit comes from doing everything wrong. The original text is:
There were plowmen in the Song Dynasty. There was a plant in the field. When the rabbit touched the plant, its neck broke and it died. Stand by and watch because you released this plant, hoping to get the rabbit back. Rabbits can't be recovered, but as a small fruit of a song. Today, the people who want to go to the former dynasty are all guarding their factories and so on.
This idiom means not making active efforts, being lucky and hoping for unexpected gains. The main truth tells us that only through our own labor can we gain something, otherwise we will eventually get nothing and leave a lifelong regret.