Do you mean "Why do people tattoo their names on their bodies?"
If so, my reason is because my brother and sister are my half brother and sister, so they have different last names. When I was born, I got my Dad's last name. My uncle on my dad's side never had kids, so as it stands, I'm the only one who can carry on the last name. It's sort of a way to pay respect to the family name.
Also, just an aside, whoever is dumb enough to get a face tattoo obviously is not going anywhere in life regardless of what they want to be. They could have the intelligence to be an astronaut, but if they're dumb enough to get a face tat...well c'est la vie.