A high score reveals an outlook that is rational and logical. A low score reveals an "emotional" or easily-influenced perspective.
Rational people accept that life has difficulties and responsibilities...but are cool and scientific about dealing with them. Emotional control and maturity often go hand-in-hand with this personality type.
Low-scorers tend to be emotional and find life more difficult than others. They often feel critical about personal qualities they dislike, or worry about what others may think of them.
It is difficult to be 100 % rational. No human being is a well-oiled machine. But it is necessary to keep an objective point of view to run efficiently in life.