It's polite to want others follow their dreams
Ted's son just told him that he wants to be a garbageman when he grows up.
Ted wants to give his son some advice.
Ted tells his son that he'll support whatever career decision that he decides to make.
Ted tells his son that he's going to be seen as a loser if he becomes a garbageman.
Ted's son feels supported by his dad, and he feels stronger in his decision.
Ted's son's feelings are hurt, and he can't believe that his own dad would say such a thing to him.