No one is ever going to "have it all together". It is very easy to fall into the trap of looking at worship leaders, preachers or anyone in a leadership role, and think that they are lucky and obviously don't have problems, or they don't understand. Also it is easy to think that you will never be able to do/be like them.
Of course people in these prominent roles do have the same trials and tribulations as everyone else and that is precisely why and how they can stand up and help bring people into God's presence. If we wait until everything in our lives is sorted before we lead worship - we will be waiting a very long time. Coupled with that, every worship leader should always be looking for ways in which to improve, enhance and enable worship.
This book helps to show the importance of the worship leader getting their heart right with God and gives some helpful and very useful tips on leading worship, song writing, choosing song lists etc.