Al-Husayn reported: Ibn al-Mubarak, may Allah have mercy on him, said, “Among the greatest of calamities is that a man knows his own shortcomings, but he does not care about them, nor does he grieve over them.”
Source: Shu’ab al-Imān lil-Bayhaqī 867
عن الْحُسَيْنَ قَالَ قَالَ ابْنُ الْمُبَارَكِ رَحِمَهُ اللَّهُ مِنْ أَعْظَمِ الْمَصَائِبِ لِلرَّجُلِ أَنْ يَعْلَمَ مِنْ نَفْسِهِ تَقْصِيرًا ثُمَّ لَا يُبَالِي وَلَا يَحْزَنُ عَلَيْهِ
867 شعب الإيمان للبيهقي الخوف من الله تعالى