The belly button (or navel) is where your umbilical cord attached when you were in your mother's uterus. The umbilical cord attached to a pancake-shaped disc called the placenta which attached to the wall of your mother's uterus. Before being born, you received all your food and oxygen from your mother through the umbilical cord and on through your navel.
When you are born, your body naturally closes one end of the umbilical cord and makes the cord fall off. Your belly button is *not* a scar or a tie that the doctor created when he/she cut the umbilical cord. The belly button forms naturally. The cut is made farther up the cord than the navel so that the belly button can form naturally. Whether you have an "outie" or an "innie" belly button has nothing to do with how the doctor cuts the cord. All of this is obvious to anyone who has had children.