Life should be molded in such a way that not for a single moment you are without Kṛṣṇa consciousness. That is real life. That is perfection. Because you have to make your life perfect by satisfying Kṛṣṇa, satisfying God. Saṁsiddhir hari-toṣaṇam [SB 1.2.13]. If you want perfection, But if you want again to become cats and dogs, which you have already passed through and now you have come to this human form of body, then you do whatever you like. But if you want to make this life perfect, stop this business of becoming repeatedly cats and dogs and trees and this and that, then this is the process: tasmād bhārata. Ekena manasā. Concentrating fully. Ekena. With one attention. No diversion. Ekena manasā, bhagavān sātvatāṁ patiḥ. Don't be afraid that "If I simply concentrate my mind in Kṛṣṇa, then how other things will go on?"
No. Bhagavān sātvatāṁ patiḥ. He is very careful about His devotee. Kṛṣṇa, God, is giving everyone's food, but that is according to karma, according to his quality and position. He's getting food. Just like hog is getting food, but he cannot get more than stool. He cannot claim, "Give me halavā." No, that's not possible. You must eat stool. Because you are, by your karma, you have got this body, hog, you must eat stool.
Prabhupada's lecture - Śrīmad-Bhāgavatam 1.2.14 Los Angeles, August 17, 1972