A student of Rabbi Nochum Zev Ziv once erred in the pronunciation of a word when publicly repeating the Amidah prayer. Someone pointed out the correct pronunciation, and the student repeated the word accurately. However, the student became confused and nervous and made many more errors.
After the prayers, Rabbi Nochum Zev approached him and said, "How is it possible to be so arrogant? Do you think you are so perfect that you cannot possibly make any mistakes?"
When I told the above story to someone, they asked, "Won't the student feel even worse and more upset by the fact that his teacher told him he was arrogant?"
It depends on how such a message comes across. If said with understanding and concern, the message is, "I care about you. Why do you have to make yourself so upset over a minor error? Of course, you are fallible and make mistakes. Expect to make mistakes and keep trying to improve, but do not feel devastated when you err."
(Imrai Daas, p.218; Gateway to Happiness, pp.130-1)