Why does the rukie scare the master?

If  the master is focused on passing on his skills he is bound to be surprised that the rukie has his own uniqueness. I have a brother who is a well renowned professional in his field. What surprises many about him is that they knew not and still don't know a lot about him. He is a survivor just like me and he trains himself outside the normal curriculum of his profession. The life skills we have comes not just from what we do but where we have been and where we want to be.