com ‧ pla ‧ cen ‧ cy /kəmˈpleɪs ə nsi/ BrE AmE noun [uncountable]
a feeling of satisfaction with a situation or with what you have achieved, so that you stop trying to improve or change things – used to show disapproval:
Doctors have warned against complacency in fighting common diseases.
Despite yesterday’s win, there is clearly no room for complacency if the team want to stay top of the league.