Your criticism is meant in the best possible way, as a way to show someone the light and the error of his ways. Before you can even begin to pat yourself on the back, however, the recipient of your grand advice is responding strangely.
Rather than a grateful demeanor and gentle tone, the object of your oh-so-valid point is glowering and, frankly, appears to be growling.
Perhaps it's time to review a few golden rules about criticizing others.
Set the tone: Rein your bull-in-a-china-shop-like tendencies and conjure up some phrases to help you ease into the topic. Good openers include "It seems to me ..." "I could be wrong, but ... " or "I'm sure you've already considered this ... "
Be empathetic: Do not be emotional. There's a huge difference. Emotions can be arrogant, blunt or patronizing. Empathy allows you to be compassionate. It helps you remember what it's like to be vulnerable or under what feels like a verbal attack, and will help you avoid doing the same to someone else.
Focus on facts: You have an opinion. And if you're in a position of authority -- whether in an interpersonal or professional relationship – you're accustomed to having that opinion matter. When you're lobbing criticism, however, it's more effective to focus on the facts behind your position. Instead of telling your subordinate, "I don't like this proposal," explain what information is missing.
Look to the future: Criticism can be framed in a positive light, especially if you're presenting it in a forward-looking way. So your employee made an error with the company's biggest client, one that has you eating your hat as a sign of regret. It's perfectly reasonable to talk about the process and where it broke down, but focus on how it can be improved next time. The best way to have this conversation? In person. If you can't do that, then pick up the phone or schedule an online conference call. Just don't deliver it by e-mail where it's nearly impossible to infer tone and attitude. The same goes for family issues. Don't criticize by text or social media where you'll likely end up in war of words [sources: Bonander, Poulsen].
Finally, ask yourself how important is this issue? If it is a personality quirk or mistake the person has made but already taken steps to correct, it might be better to just let it go.