How to improve efficiency

I always find it difficult to keep struggling performers on par with others. Covering them with lots of examples, reinforcement of content that needs to be acquired with you getting experienced at your work force. But, at times things doesn't change. It hurts, drains you, stretches you and then you are de-motivated. All this happens to me always ... Why ? No answer. But, I always looks forward how to mobilize resources, come up with innovative ways to make them learn in a manner they want to learn and finally what I want to make them learn ;=)