Difference between Optimistic and Complacent

OPTIMISTIC vs COMPLACENT: ADJECTIVE

Expecting the best in all possible ways.
Hopeful; sanguine.
Of or pertaining to optimism; tending, or conforming, to the opinion that all events are ordered for the best.
Expecting the best
Expecting the best in this best of all possible worlds

Contented to a fault with oneself or one's actions
Apathetic with regard to an apparent need or problem.
Uncritically satisfied with oneself or one's achievements; smug.
Self-satisfied; contented; kindly.
Eager to please; complaisant.
Satisfied with the current situation and unconcerned with changing it, often to the point of smugness.
Contented to a fault

Of, pertaining to, or characterized by optimism; disposed to take the most hopeful view of a matter; hopeful; sanguine.

Accompanied with or springing from a sense of quiet enjoyment; gratified; satisfied: as, a complacent look or smile.
Civil; kindly; giving pleasure. See complaisant (now generally used in this sense).

Satisfied, Convinced, Confident, Hopeful, Pessimistic, Starry eyed, Rose colored, Affirmative, Cheerful, Pollyannaish, Positive, Rosy, Bullish, Upbeat, Sanguine

Passive, Happy, Condescending, Satisfied, Confident, Cavalier, Optimistic, Smug, Arrogant, Indifferent, Apathetic, Vigilant, Self satisfied, Content, Contented

Satisfied, Convinced, Confident, Hopeful, Pessimistic, Starry eyed, Rose colored, Affirmative, Cheerful, Pollyannaish, Positive, Rosy, Bullish, Upbeat, Sanguine

Passive, Happy, Condescending, Satisfied, Confident, Cavalier, Optimistic, Smug, Arrogant, Indifferent, Apathetic, Vigilant, Self satisfied, Content, Contented

Pandemic experts are starting to sound increasingly optimistic.
Correcting for optimistic prediction in small data sets.
Still, ultimately he is guardedly optimistic about mechanism.
Studies conducted in humans show less optimistic findings.
This is an optimistic skyline of New York.
These results are related to the hypothesis of optimistic bias, which states that drinkers are overly optimistic about probabilities of adverse consequences from drink.
In an optimistic locking session, you must take responsibility for coherence and consistence by following an optimistic locking protocol.
SD, through the slightly optimistic last observation carried forward method, to the optimistic complete case analysis.
Are you more optimistic or less optimistic than you were a month ago?
That was idealistic and optimistic, a way too optimistic hope.

But such recognition has not made Gallagher complacent.
Realistically complacent due to basal disinfection mayan cuts.
But dun tell him wait he get complacent.
From what complacent depths are such judgements made?
Europe has been complacent about its own defense.
This leads us to a complacent political culture.
Complacent people are thoughtful and considerate of others.
Advantage Ferrari but Schumacher not complacent. - Yahoo.
Sydney Carton looked at his punch and looked at his complacent friend; drank his punch and looked at his complacent friend.
Of complacent civilians, there are those who are passively complacent and those who are actively complacent.