The easy path to destruction in one’s life and other’s life is complacency. It can be easily misunderstood as happiness and contentment. However, it is a demon in disguise. It makes one obstinate and easy-going. One stops growing when he has such an attitude in life. It is a brother of self-righteousness.
Complacency is a feeling of smug or uncritical satisfaction with oneself or one’s achievements. This link will definitely shed much light into the harmfel effects of this attitude.
some useful links:-
This video showcases craftfully the dangers of complacency.
The following video shows how it ruins relationships.
The video below shows another truth about it.