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 867
عن الْحُسَيْنَ قَالَ قَالَ ابْنُ الْمُبَارَكِ رحمه الله مِنْ أَعْظَمِ الْمَصَائِبِ لِلرَّجُلِ أَنْ يَعْلَمَ مِنْ نَفْسِهِ تَقْصِيرًا ثُمَّ لَا يُبَالِي وَلَا يَحْزَنُ عَلَيْهِ
867 شعب الإيمان