I understand, but it's also unfortunately unrealistic to expect that someone who is already an expert in something will also become an expert in teaching. When

I understand, but it's also unfortunately unrealistic to expect that someone who is already an expert in something will also become an expert in teaching. When you are an academic, besides your teaching you need to be constantly updating your knowledge of the state of the art and pushing the boundaries to get published and stay relevant in your field. It's hard to also focus on learning teaching skills which are, sometimes, very unorthodox and not straightforward. Also, factor in that those who teach teaching are also sometimes not good teachers, and are also researchers, and will also need to stay updated with research, and will also try to push unorthodox, unvalidated teaching methods to their students... it's complicated.