Prabhupāda: If you miss this opportunity of human form of life... Because we do not know when death is coming. It is not that because I am old, I am nearing death, and you are young, you are not nearing death. Who knows that you may die before me? So there is no certainty. So the principle is that because this human form of life is so important to perfect oneself in Kṛṣṇa consciousness, he should not waste even a minute.