Acharya Prashant explains that the mind remains attached to worldly pleasures despite knowing the transience of the body and the world because it is driven by fear. This attachment, or 'liptata', is an attempt by the ego to cover itself with external layers to feel secure and complete. The speaker clarifies that the realization of mortality often leads people to the wrong conclusion of renouncing the world out of frustration, much like a child throwing away a toy because it is not exactly what they wanted. This type of renunciation is still a form of attachment because the mind remains preoccupied with the world it is trying to escape.