What are the acceptable reasons to provide feedback to a member of your team (or someone else)?
If you said anything other than "correction" or "praise" then you probably should read on. If you said either of those (or both) you might want to read on, anyway, or this will be a short blog week for you.
Basically, we often want to give feedback because our emotions are engaged in some way. Sometimes its positive, and sometimes its negative. But feedback really needs to be given sans emotion. Emotion can create a confusing context, and make the person receiving the feedback wonder if you're mad at him or her or the behavior you're trying to correct.
And note, I've said it before, but I'll say it again: you're never trying to correct or praise a person, but their behaviors. They can change those. they can see the behavior being praised in another and copy it, but they can't copy being the person who is praised (well, not in a non-creepy, non-stalkery way). Likewise, they personally are not a bad person, because even parents can't correct bad children, per say; they do behaviors that you don't like, just like kids. You need to give feedback to correct the behavior, so that the person can be more successful. See, your job as a manager is to make the people that work with you more successful (as I've said in earlier posts), because it only reflects good on you, and makes for a cohesive and positive team.
When giving feedback, unless there's some kind of potential emergency--"Um, Jane, mouth to mouth should be given from your mouth to his mouth, and not to his ear,"--you want to do it after you've had a chance to reflect on it, but not too far after the incident for the person in question to have forgotten about the event and/or her motivations for the choices that she made. It also gives you time to calm down if you had an emotional response (laughing my self silly is not proper when watching someone nearly kill someone else with inappropriate life saving techniques, but I might need some time to get over the giggles afterwards before I explain my feedback and press on to repair the behavior).
Typically, I give feedback that is potentially constructive (or they might view as negative) privately, and I give feedback that is praise in public. This might mean an email to a boss as well as the employee when praising them, but typically involves a face-to-face private discussion if managing a constructive conversation. Praise is rarely misinterpreted via email, and email is a good way to let someone's boss know they are doing good. Criticism, however, is completely easy to misinterpret in any way other than in person or over-the-phone; with a lack of context, its hard for some people to see you being unhappy with the behavior and not with them personally.
It can also be very intimidating to give feedback for both the receiver and the giver. However, if you are managing people, it's part of your job to help them be better and more productive workers. So, feedback comes with the territory. To get over the feeling of intimidating, make yourself a small list and follow it when talking to them. If they react negatively to your discussion, remind them that its the behavior you'd like to see changed, and that you are only giving them feedback because you actually like them, personally (or at least like working with them). Remember: it's not about you v. them, it's about you and them v. the behavior that may be holding them back.
I would also say to be careful with praise, too. Some people do not do well under the spotlight. Get to know folks and find out if they can handle public appreciation; if not, you might want to keep it private so they know you know, but don't have to worry about other people knowing and judging.
So there you go: one of the most powerful tools in a manager's toolbox: feedback. Use it wisely, and with as little emotion as possible, and you'll see amazing results over time.