good advice is harsh to the ears; honest advice is often unpleasant
A yojijukugo proverb meaning that sincere, well-meaning advice can be hard to accept because it points out one's faults. Used in formal or literary contexts.
They say good advice is harsh to the ears, but his stern criticism really helped me.
A similar proverb meaning 'good medicine tastes bitter,' emphasizing that beneficial things are often unpleasant. 忠言逆耳 focuses specifically on advice.
From Classical Chinese 忠言逆耳, “faithful advice offends the ear,” an expression found in early Chinese historical literature for the unpleasantness of honest counsel.