Muṇḍaka Upaniṣad · 1.2.9

अविद्यायां बहुधा वर्तमाना वयं कृतार्था इत्यभिमन्यन्ति बालाः । यत्कर्मिणो न प्रवेदयन्ति रागात्तेनातुराः क्षीणलोकाश्च्यवन्ते

avidyāyāṃ bahudhā vartamānā vayaṃ kṛtārthā ity abhimanyanti bālāḥ | yat karmaṇo na pravedayanti rāgāt tenāturāḥ kṣīṇa-lokāś cyavante

The immature, living in various ways in ignorance, think: We have accomplished our purpose. Due to attachment, they do not understand the result of their actions — agitated, decayed, they fall from their worlds.

The trap of complacency: believing one has arrived when one has barely begun.

Avidyāyāṃ bahudhā vartamānāḥ — living in various ways in ignorance. Different paths, all erroneous for lacking clear vision.

Kṛtārthāḥ — have accomplished their purpose. The premature self-evaluation based on external achievements.

Bālāḥ — the immature, the children. Not by age but by incomplete spiritual development.

Rāgāt — due to attachment, passion. Desire that clouds discrimination.

Karmaṇo na pravedayanti — they do not understand the result of their actions. They ignore the law of cause and effect.

Aturāḥ kṣīṇa-lokāḥ cyavante — agitated, decayed, they fall. Suffering and the fall from earned worlds.

The cycle of complacency, fall, and renewed effort repeats until wisdom arises.