I am not sure if this is true, but I would say that the schedule is also a factor. Head coaches have a really difficult schedule, especially for older kids. Usually, they have training every morning from 5 a.m. to 7 a.m. or from 5:30 a.m. to 7:30 a.m. and every evening from 4 p.m. to 6 p.m. It is very difficult to be a coach for a woman who gets her kids ready for school and looks after them after school, because that is when the training sessions take place.
On March 4th, 2013. See this statement in context.