Allah the Almighty mentions to us in the Qur’an Paradise, Hell-fire and Resurrection a lot so that people remember that the worldly life is a short and fleeting life and that the afterlife is the eternal life. And those who do not believe, the tyrants and all those who commit evil things are warned that the torment of the afterlife and the torment of hell will be a painful torment.
And because Allah the Almighty is Just and Merciful to the servants, then He would not have tortured anyone until He sent Him a warning. That is why He sent the prophets and sent with them the heavenly books, and for this same reason the Qur’an mentions fire and torment a lot, to remind people of Allah and the Afterlife and to be a warner to the people.
(وَمَا أَهْلَكْنَا مِن قَرْيَةٍ إِلَّا لَهَا مُنذِرُونَ (﴿﴾ ذِكْرَىٰ وَمَا كُنَّا ظَالِمِينَ ﴿)
الشعراء 26: 208-209