China Naming Network - Baby naming - Which eight-character idiom is used to describe feeling depressed when you see your shortcomings in grade three?

Which eight-character idiom is used to describe feeling depressed when you see your shortcomings in grade three?

No gold is pure, no one is perfect ―― everyone has his fragile side; Nobody is perfect.

From Dai Song Fugu's "Xing Xing": "Gold has no color, but white jade has slight defects. I am not prepared for help, I wish the old gentleman a family. "

It is also a metaphor that you can't ask a person to be free from faults and mistakes.

There are no perfect people in the world, and gold is not all red. People have advantages and disadvantages.