Never criticise people – only the behaviour. Always separate the person from the behaviour.
We all make mistakes, we all do and say silly things from time to time.
Refrain from labelling and criticising people, especially in public.
If you have something negative to say, try to re-frame it in the positive. For example, instead of saying “you’ve screwed up today” say “you had done much better yesterday and we want to see more of that tomorrow”.
If you want help achieving your career goals faster and without too much stress, I offer help and support through the Achieve Your Career Goals Faster workshop: https://www.focusplanachieve.com/workshops/achieve-your-career-goals/