If a movie receives mostly unfavorable reviews, that means the reviews were not good because most people who saw it didn’t enjoy it at all.
The word unfavorable combines the prefix un-, meaning "not," with the word favorable, referring to something "positive or beneficial." When something is described as unfavorable, it suggests that the situation isn’t going your way — like when the weather forecast predicts rain for your outdoor event. An unfavorable outcome can lead to frustration, disappointment, or unmet expectations, signaling that circumstances aren’t aligning in your favor.