不利 (bù lì) describes a situation or condition that is unfavorable or disadvantageous, often used with 对 (duì) to indicate what is harmed. It focuses on lack of advantage, unlike 不良 (bù liáng) which describes a bad quality or habit, and 有害 (yǒu hài) which directly means 'harmful' (e.g., to health). 不妙 (bú miào) is more about an ominous or worrying turn of events.