Shavechads, how many times do you have to do over the tough to reach spots?

Like around the larynx, at the edge of the jaw. My father claims I'm doing it wrong for going it over 2x or 3x and it'll damage my skin(true tbh I do cut myself frequently). But if I go ever it just once little bits remain and when I'm caressing my face afterwards to feel how smooth it is they hit my finger and feel irritating.