Nothing else so inspires and heartens people as words of appreciation. You and I may soon forger the words of encouragement and appreciation that we utter now, but the person to whom we have spoken them may treasure them and repeat them to themselves over a lifetime
Dale CarnegieBegin with praise and honest appreciation. Call attention to people's mistakes indirectly. Talk about your own mistakes before criticizing the other person. Ask questions instead of giving direct orders. Make the fault easy to correct. Make the other person happy about doing what you suggest.
Dale CarnegieThere is a certain degree of satisfaction in having the courage to admit one's errors. It not only clears up the air of guilt and defensiveness, but often helps solve the problem created by the error
Dale Carnegie