A Good Dancer is not necessarily a Good Teacher
Of course you want to make sure your dance teacher knows how to dance but it doesn't mean he has to be world champion to be a good teacher.
Teaching dance require a lot of psychology, physiology and patience. Knowing the students , how they behave, how they learn.
In the past 40 years I've met so many great dancers and choreographers but few of them became teacher. And the most popular reason is because they said they have no patience.