Explain the title of this chapter, "I Don't Check My Mother At The Door."

Lance competes in the World Championships in Oslo, Norway. His mother sits in the rain for seven hours watching him race. At these championships, Lance becomes the youngest winner of a world cycling title. He is invited to meet the King of Norway. He brings his mother with him, but they are stopped at the door and told that the King will meet Lance only. Lance says, "I don't check my mother at the door," and he turns to leave. Officials stop him and then allow his mother to go in with him.