We learn from our mistakes... but we truly show we learn by fixing them. With an artist's eye we look, study what's wrong, fix and mend it. In life, if we make a mistake, we should not leave it. We fix the issue, apologize to the offended and try to never repeat it again.
As teachers, we correct them often. Then later, we have to look for follow up evidence of lesson learned. Did they find the issues themselves and correct them independently? Do they fix things only when we point them out, or are they wise enough to do it on their own?