Sometimes trainers simply do not know enough about their subject matter to be effective trainers. There are two reasons for this. The trainer or organizations subscribes to the myth that anybody with training skills can teach any topic to anyone. Or, a trainer agrees to deliver training in a subject area he or she is unqualified in for business reasons, ignorance, or is simply told to do so by his or her boss.
Regardless of the reason, the clients suffer through mundane, cookie cutter training offered by someone who can't answer questions beyond the basics for the topic, and the trainer has to deal with embarrassment about having to deliver something where he or she lack confidence.
There is a solution, and that is a) for training consumers to insist that the trainer have an indepth knowledge and/or experience with the topic, b) training organizations and departments realize that expertise IS important, and stop asking incompetent people to deliver training, and c) trainers step up to the plate and learn to say NO, to either their bosses, or potential paying customers when asked to deliver training without proper knowledge and/or experience.
It's a professional obligation.