Giving Compliments that Count
Praising is almost always welcome, and is very seldom done - much like saying "thank you," it's something that's easily neglected, but very powerful when remembered.
The difference between praise and flattery is that the former is earned: a person is praised for something out of the ordinary. Praise also becomes flattery when it is taken too far.
Praise is also cheapened when it's handed out too often - to tell everyone that they've done a "good job" makes the complement a meaningless verbal tic. Be specific about why you are praising someone.
Also, "praise in public" is a general principle that has exceptions: some individuals are embarrassed by attention, and feel awkward when singled out.
Don't mix praise with criticism - if both are called for, deliver the praise last (criticize, then praise), or better still, deliver them at separate times.
Do not praise someone, then make a request of them. It seems manipulative. Again, do these things at separate times.
Praise is especially important if you are a manager. In many cases, employees receive only negative reinforcement (and often develop a sour attitude toward their manager) - be just as quick to let people know when they've done well.
When accepting praise, be gracious. It's common for a person to want to appear humble when praised - they may make some remark to lower themselves, or insist that something was "no big deal" - which suggests that the person is giving praise inappropriately.
Also, do not feel then need to return complements - it's much like favors: accept graciously, then shut up.
EN: Again, whether it is appropriate to make personal remarks about others, even in a positive way, requires sensitivity to culture.