Motivation is Owned by the Individual
Motivation is a slippery slope. I believe Wlodkowski who says: one cannot directly motivate another since motivation is owned by the individual; it comes from within us. It's the same as telling one to stop thinking abut sex. You have no control over that person's thinking, though you may provide an ambiance of sorts to do so; the same applies to motivation.
However, the leader can foster motivation by addressing two questions:
1. What do you need that you're not getting?
2. What can I do to make this relationship better, different, or more...(you choose the word)?
Then listen carefully to the response. Most, if not all want to be recognized, validated, and respected. Performance expectations and metrics must be crystal clear; finally, leaders must be consistent in their behavior--no Jekyll and Hyde--of integrity, trust, rewards, and punishment.