They were born among lower animals or driven to hell and again and again had to suffer the pain of rebirth in this wonderful world on account of their vicious deeds.
अशुभैः कर्मभिः पापास्तिर्यनिरयगामिनः। संसारेषु विचित्रेषु पच्यमानाः पुनः पुनः॥