Pointing fingers is of no use to anyone; nudging people in the right direction is much better.
When you are criticizing someone for doing something you believe is not appropriate, you take on the responsibility of wholeheartedly appreciating them for their achievements and that, with double energy.
When someone does something worthy of praise , don’t let personal bitterness over past issues dilute the vigour of your appreciation for them. That would be unfair.
Criticism is a debt, which needs to be paid off with applause. It takes a toll not only on the one who is being criticized but also on the one who is criticizing. Criticism should be given and taken wisely.
You have to outweigh the debt of criticism with appreciation, whenever possible.
Even when you have negative feedback, offer it as a suggestion and not as criticism. that is a healthy thing to do, Because the intent should be to help and not to hurt, not punish but correct.