BHAGAVAD GITA AND DUTY

"Better one's own duty, though devoid of merit, than the duty of another well discharged. Better is death in one's own duty; the duty of another is productive of danger."- Sri Sankaracharya's interpretation.
"There is more happiness in doing one's own work even without excellence than in doing another's duty well.Each one must try to understand his psychophysical make-up and fuction in accordance with it."- Dr S. Radhakrishnan's explanation.
After reading these lines I am quite clear that they meant a man must do what is in accordance with his specific temperament and morality.