The original production source and speaker of this recording are not reliably documented. Online, the Spanish phrase functions as a reaction meme for behavior that feels automatic, habitual, or difficult to stop. “Carnal” is colloquial Mexican Spanish for a close friend or brother, while “es la costumbre” means “it’s a habit” or “I’m used to it.” The line remains useful because it supplies an instant comic excuse after a repeated mistake, impulsive action, or familiar prank.