Why do they feel that way? One reason is that they live in a world full of hatred, war, and suffering.
أَحَدُ ٱلْأَسْبَابِ هُوَ أَنَّهُمْ يَعِيشُونَ فِي عَالَمٍ مَلِيءٍ بِٱلْبُغْضِ وَٱلْحُرُوبِ وَٱلْأَلَمِ .‏