His conduct towards people bespoke his low origin.It is clear that the Dhana Nanda dynasty was very unpopular among the people and the neighboring states, few possible explanations of the unpopularity could be their varna, Nanda Kings were said to be of shudra caste and the other reason being their financial extortion.It is therefore no wonder that he was "destested and held cheap by hissubjects".
The people of his kingdom feared him so much that they began taking refugee far away from his kingdom in caves and under trees.
The disaffected element found a new leader on Chandragupta who overthrew the nanda dynasty, and laid the foundation of the Mauryas. The exact circumstances surrounding the death of Dhana Nanda are unclear. Some accounts suggest that Dhanananda was killed by Chandragupta Maurya, the founder of the Mauryan Empire, after the latter captured Pataliputra, the capital of Nandas. Other accounts however suggest that after Pataliputra was stealthily captured by Chanakya, Dhana Nanda was sent into exile and was never heard of again.
It is also suggested that Dhana Nanda was killed on Chanakya's orders during exile, thus clearing the path for Chandragupta's kingship.Some other accounts also suggest that as Dhana Nanda had taken to Buddhism before exile, he renounced life completely after his clan was wiped out in a coup; thus not being a threat to Chanakya's plans and therefore was allowed to live.
Image: google.references: wikipedia2.Basic facts on history