Buddhists, why do you have to suffer to achieve Enlightenment?

You have to see the truth about suffering to achieve enlightenment, sometimes seeing or experiencing suffering can lead to realization of the truth. The truth is that birth is suffering, aging is suffering, illness is suffering, death is suffering; sorrow, lamentation, pain, grief and despair are suffering; union with what is displeasing is suffering; separation from what is pleasing is suffering; not to get what one wants is suffering. It is craving which leads to renewed existence and suffering, accompanied by delight and lust, seeking delight here and there, that is, craving for sensual pleasures, craving for existence, craving for extermination.