It isn't pre programmed to what I understand. All it does is guess what your drawing looks likes based on other peoples drawing, and continues to guess until it is correct. So when you drew a car with no siren, it's guesses could have been truck, car, police car. Since it guessed police car, it got the answer correct. The program wasn't told you had to draw a police car. That would be silly. Why would they create this and lie about how it works? What would be gained?