The term was originally used to indicate a person’s social status, usually referring to the rulers’ subjects or those low in social ranking. Later generations also used the term to indicate one’s moral standard in a disapproving way. Those of base character were called petty men as opposed to men of virtue. A petty man only pursues his personal interests or profits, even by violating morality and righteousness; and such people have no understanding of or regard for Dao.
A man of virtue understands and observes what is morally right; while a petty man only has his eyes on and goes after what brings him personal gains. (The Analects)
They are petty men because they only seek ease and comfort of the moment and pursue personal gains. (Zhu Xi: The Analects Variorum)