The customer of the Paradise has been less since the time of Hazrat Adam, because to people, its price seems expensive; they have to present prayers, fasting, Khums, purity, inward purity, justice, affection and kindness, and have to avoid ill-gotten things, these are the price of Paradise and most people have not felt like paying this price since the time of Hazrat Adam. They understood that the Hell is inexpensive and can be bought by adultery, usury, oppression and murdering; in fact, they buy it by paying such price.
source : erfan.ir