My Nini bird does the flop when he doesn't want to go back into his cage. It has become a bit of a game now. He flops, I swirl him around until he is upright and then he flops again...over and over....I gave up flipping him back up when I need to put him back in his cage and just put him in his cage on his back. He looks at me with a "What the heck did you just do" look and after 20 seconds or so he gets up.