I always get frustrated if I am calling a wrong number. They are rude sometimes especially if you attempted calling another number but it still the same number you called earlier. The telephone directory is also not updated and the informations are not changed unless the subscriber request to change it.
Reverse Phone Registry helped me in my problem. You can initially check if the owner of the number is your friend by giving you the owner's full name, address, relative and background information and etc. Now, I don't get rude answers if I call because I have already checked the number.