měi zhōng bù zú 
		everything is fine except for one small defect (idiom); the fly in the ointment
		 
		
		
														
		
		
			 
		
				
		
			měi yī gè rén dōu yǒu měi zhōng bù zú de dì fang 
		However excellent, everyone has his defects.
There is always a fly in the ointment.
cf idiom 美中不足[měi zhōng bù zú], everything is fine except for one small defect