In Buffalo every few years, the teachers are required to take proficiency tests that the high school students are required to pass to graduate from high school and the teachers fail them at an alarming rate. Of course, there is a hue and cry from the teachers unions but it is embarrassing nevertheless.
Bigbird might have had the knowledge to teach. She might have known the mechanics to teach. But she lacked the passion or desire to teach. How can someone teach another, if they don't respect or love the other?