When conveying negative news, depersonalize the message. For example, instead of saying, “You failed to notice…”, consider “May I point out that…” or “Another consideration is…”. One way of depersonalizing is to use passive voice. For instance, instead of using active voice by saying “Your action caused us to lose a $10,000 sale, say, “By delaying the order, a $10,000 sale was lost.”
Depersonalizing the message creates a more objective, tactful tone. Additionally, using passive voice focuses on the behavior (delaying the order), rather than on the person.