The key part of learning is criticism. That's what really makes it work. The basic concept is we take fallible ideas, with mistakes in them, and we correct mistakes using criticism. Thanks to the criticism, we improve the ideas.
Criticism is the primary tool for finding and fixing mistakes. And it's the primary tool for learning and for solving problems.
Some people are scared of criticism. They feel bad because they aren't good enough. They don't want to have flaws. Or they've had bad experiences with criticism.
The best way to think about it is like this: Everyone has flaws whether they are pointed out or not; criticism is just about finding them and doesn't actually create any problems. It's better to know about problems than to overlook them. Once you find out, you gain the opportunity to do something about it.