I hate callers with zero numbers & unknown name

I hate that number which called up a while ago. Why? Aside from its zero numbers it’s also unknown name. GRRR! I answered the phone but I didn’t speak. Until I’ve heard a voice which I can’t hardly recognize if he is speaking English or Spanish. After that, I answered asking him the name of the person that he is looking for. Then, I said that there is nobody living with that name and I don’t know that person either. GRRR! I hate that call(s)! Why are they have zero numbers and at the same time unknown name? Are they hiding something? Or are they trying to fool other people who are innocent? I don’t get the point of why they are hiding themselves with zero numbers and unknown name.