I'm a diamond in the rough like a baby in the trash
Similar to “needle in the haystack”, Wayne is a “diamond” in the rough (other rappers).
His choice of metaphor is disturbing, recalling the numerous cases of young mothers (often from poor/minority backgrounds) who have thrown away their children after accidental pregnancies, not knowing what to do or how to take care of them. This ugly reality of ghetto living brings the playful/boastful metaphor back down to earth.
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