surprisingly difficult in a lot of cases when you when you shape your reward function your agent will find some very surprising way to make sure that it's getting a lot of reward but not doing at all what you wanted to do and in a sense the policy is just overfitting to that specific reward function that you designed while not generalizing to the intended behavior that you had in mind and there's a lot of funny cases where reward shaping goes terribly wrong so here for example the agent was trained to do jumping and the reward function