Action in Kṛṣṇa consciousness has to be executed in accord with the examples of previous bona fide devotees. This is recommended in the 15th verse. Why such action should not be independant will be explained in the text to follow.
To act in Kṛṣṇa consciousness, one has to follow the leadership of authorized persons who are in a line of disciplic succession as explained in the beginning of this chapter. The system of Kṛṣṇa consciousness was first narrated to the sun-god, the sun-god explained it to his son Manu, Manu explained it to his son Ikṣvāku, and the system is current on this earth from that very remote time. Therefore, one has to follow in the footsteps of previous authorities in the line of disciplic succession. Otherwise even the most intelligent men will be bewildered regarding the standard actions of Kṛṣṇa consciousness. For this reason, the Lord decided to instruct Arjuna in Kṛṣṇa consciousness directly. Because of the direct instruction of the Lord to Arjuna, anyone who follows in the footsteps of Arjuna is certainly not bewildered.
It is said that one cannot ascertain the ways of religion simply by imperfect experimental knowledge. Actually, the principles of religion can only be laid down by the Lord Himself. Dharmaṁ hi sākṣāt-bhagavat-praṇītam. No one can manufacture a religious principle by imperfect speculation. One must follow in the footsteps of great authorities like Brahmā, Śiva, Nārada, Manu, Kumāra, Kapila, Prahlāda, Bhīṣma, Śukadeva Gosvāmī, Yamarāja, Janaka, etc. By mental speculation one cannot ascertain what is religion or self-realization. Therefore, out of causeless mercy to His devotees, the Lord explains directly to Arjuna what action is and what inaction is. Only action performed in Kṛṣṇa consciousness can deliver a person from the entanglement of material existence.