BLAME AND SELF-ESTEEM
When I was an Airline Pilot I was responsible for all flight operations, whether good or bad. If you are taxing into the gate and your wing clips a baggage cart, it is the Captain's fault. It doesn’t matter if the lineman steers you the wrong way or not. What the lineman needs is not to be hammered with threats but more training on how to bring an aircraft in.
Blame comes from lack of self esteem.