Motivating people is one of the most important skill for leadership but is often neglected. The key thing to remember is that we are social animals and people are more important than your profit or score. Motivating people will not only make the work environment better but also increase profit.
According to me, the best way to motivate with leadership is Lead by Example. Show people what they can achieve by doing what they have to with the same determination as you (you ought to have determination for that though ; - )). Show them that they too can achieve more.
Remember, "the job of leaders is not to be in charge, it is to take responsibility of those that are in your charge" -Simon Sinek
There is a story that Simon Sinek told in one of his sessions, It's some times called the four seasons story. You can look this video for the story (starting at 4:48 roughly)
But in short, this story shows that the same employee can work very differently under different leaders. So, a leader must show that the person responsible for the job is cared for. Their needs are taken care of and they are explained that what they do has meaning and is really important.