Delegate and Teach, Please

The customer forgets to order the packaging materials for their product to be sent to us again! She blames it on her new assistant. We think that it is not the assistant that is to be blamed. Maybe she did not teach the assistant well. Now I know why she has so much work because she just does not know how to delegate her job. And when she delegates, she does not teach. Assuming that others will be like her, full of initiative.