When people say, "Those who can't do, teach."

This phrase is meant to devalue teachers and frame them as losers who failed out of "real" professions. This is wrong for two reasons. Firstly, in my experience the best teachers are extremely intelligent and knowledgeable in their fields, but chose to teach because they valued their own education and want to make a real difference in their community. They are not incapable of being researchers or industry workers, they simply choose a more rewarding path for themselves. Secondly, teaching is a skill-intensive career that requires years of learning and practice to perform well. It is not an easy out for talentless losers, and in fact most scientists, authors, and other experts lack the skills necessary to be a teacher. I think that people who use this phrase reveal their ignorance and promote the devaluation of education that is already eating away at society.