In heaven there is perpetual happiness. Both happiness and misery exist in this world. In hell there is only misery. Happiness is, therefore, the greatest object of acquisition.
नित्यमेव सुखं स्वर्गे सुखं दुःखमिहोभयम्। नरके दुःखमेवाहुः सुखं तत्परमं पदम्॥