The Bhagavad Gita · Chapter 18 · verse 18.47
Better is one's own duty, though imperfect, than another's duty well performed. Performing the work fitted to one's own nature, one incurs no sin.
Sanskrit (Devanagari)
श्रेयान्स्वधर्मो विगुणः परधर्मात्स्वनुष्ठितात्। स्वभावनियतं कर्म कुर्वन्नाप्नोति किल्बिषम्॥
Transliteration
śreyān sva-dharmo viguṇaḥ para-dharmāt sv-anuṣṭhitāt; svabhāva-niyataṁ karma kurvan nāpnoti kilbiṣam
English translation
Better is one's own duty, though imperfect, than another's duty well performed. Performing the work fitted to one's own nature, one incurs no sin.
Meaning — what the verse is actually saying
The Gita returns to svadharma in its final chapter. Doing the work fitted to your nature, even imperfectly, is the right path. Performing someone else's work, however well, is a kind of self-betrayal.
Modern practice — what to do today because of this
When evaluating a career move or life pivot, do not ask "is this a better-quality opportunity?" Ask "is this work fitted to my nature?" The first question chases other people's metrics. The second is the only one the Gita treats as serious.