他不好只是谁都代替不了她不好只是谁都替代不了
[tā bù hăo zhĭ shì shéi dōu dài tì bù le tā bù hăo zhĭ shì shéi dōu tì dài bù le]
This indicates the irreplaceability of certain individuals despite recognizing their flaws ('He is not good but no one can replace him, she is not good but no one can replace her'). The user feels an incomparability for specific people who, regardless of imperfections, hold irreplaceable places in their hearts.