Better is one’s own duty deficiently performed than the duty of another well performed. Better is death in one’s own duty, for the duty of another leads to fear.

Classic verse on svadharma. One’s own duty (sva-dharma), even viguṇaḥ — deficient — surpasses another’s (para-dharma) performed perfectly.

Nidhanam — death — in sva-dharma is preferable. Why? The duty of another is bhayāvahaḥ — producer of fear — because it implies alienation from being. Arjuna must fight, even though killing repels him; fleeing to the ascetic life would be para-dharma for him.