Ain’t no such things as halfway crooks

Phrase from Mobb Deep’s “Shook One’s Pt. II” 1995, meaning that you are either a crook (thief) or you aren’t

What Mobb Deep is referring to as halfway crooks are rappers who act hard but really aren’t

“Scared to death and scared to look, they shook, ‘cause no ain’t no such things as halfway crooks”