Feedback can be learnt
Another point to remember is that vague, feelgood feedback doesn't really help either. It's much more motivating to hear 'Thanks for updating me on XYZ. Its really useful for me to know whats happening', than 'You're a great guy, keep up the good work'.
Vague positive feedback, because its not specific, is unhelpful and can also sound insincere.
So when you're giving feedback, or completing a 360 for a colleague, make sure you give great examples from real life.