Many people dislike change.
I remember when nitrox appeared in the UK, many BSAC National Instructors just refused to accept its existence. For some their rejection stemmed from the fact that here was a new approach and they, the gurus of leisure diving, would have to join the queue to go back to the classroom. The open-minded accept that they can learn from others, and that what might once have been the best way is no longer necessarily so. Many BSAC branches have modern ideas and approaches to keep in tune with the wishes of current and potential members. This helps them provide a high quality of service to their members, and get more to join.