Keeping promises is hard. It requires us to do things we don't want to do. But keep those promises you must do. Otherwise, do not make them in the first place. But since you have made them, you must keep them, especially if it would benefit all those involved including yourself.
If leadership was easy, everyone would be great leaders. Leadership unifies a team to do what it does best. It takes patience and understanding -- it takes empathy. Having the skill of empathy allows the leader to know when to motivate and when to step back. People will do the right thing if they are the right people.