Bhagavad Gita · 18.24

यत्तु कामेप्सुना कर्म साहङ्कारेण वा पुनः।क्रियते बहुलायासं तद्राजसमुदाहृतम्॥

yat tu kāmepsunā karma sāhaṅkāreṇa vā punaḥ kriyate bahulāyāsaṁ tad rājasam udāhṛitam

But action performed with great effort by one seeking to fulfill desires, or done with ego — that action is declared to be rajasic.

— Bhagavad Gita 18.24

Source: Sacred-Texts.com (Sanskrit) + Bhagavad-Gita.io (translations)