I do understand... I don't think you understand THAT WAS ALWAYS THE PLAN. They smuggle the pigeon OUT of the prison by whatever means they have, then it gets loaded full of drugs and flies back into the prison. If the guards catch it and release the damn thing, it flies back to the prison and they can smuggle it out to load up with drugs again. This will continue happening for as long as the pigeon is alive. If you don't kill the pigeon, now you're playing pigeon games forever.