feeling calm satisfaction with your own abilities or situation, especially when this prevents you from feeling sympathy or understanding for others

They uttered self-complacent phrases about the improvement in the condition of the working class.

The idea that success spoils people by making them vain, egotistical, and self-complacent is mistaken. 认为成功就会使人沾上虚荣、自大且自满恶习的想法是错误的。