How do you give constructive feedback?
Assessing is different from giving feedback. Assessing belongs in a performance review; feedback in a performance review.
Ask questions until you clearly understand what the other person wants from you. Ask for his or her opinion about the situation. Asking open-ended questions and observing carefully will yield more than simply telling an employee how to do his or her job.
Listen in order to judge, without judging. Check that you have understood the other person correctly.
Avoid in discussion, defense or counterattack.
Create a safe atmosphere: your feedback will be lost if it makes the other person feel bad or makes them look ridiculous to colleagues.
Performance feedback is informal and collegial. State what you will do with the other person's question. Be specific and clear in your feedback.