Reality struck I seen the white car crash
Hit the light pole two nigga's hopped out on foot and dashed
This was the moment Kendrick realized he was living in a warzone, or a “m.a.a.d. city”; he saw a car crash into a pole (presumably stolen / from a police car chase since that shit happens in L.A. on the regular) and the guys inside hoofed it. This works as a foreshadowing of Kendrick’s eventual criminalization, such events in the hood lifestyle seeping into his clean, school-grad mind.
He calls it a white car, a reference to the fact that the car was carrying cocaine, hence after it crashed the two men hopped out and ran, because they had coke and if the police came to investigate they would be caught with cocaine.
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