Source
WHO IS A LEADER?
A leader is "a person who influences a group of people towards the achievement of a goal".
In this above definition it says a leader is a person and from my experience in the time spent in this life I got to realize everyone have their vices, and a leader can be looked up to but we really shouldn't be too quick to judge when a leader make certain mistakes because just like us they are humans.
Source
let's take a look at Moses, he was the face of God to the people of Israel, he was a man so dear to God that God listened to him and never killed the Israelites but yet he had his own vices, he made certain mistake and almost ran shot of God's favor, There are also other great men of God who also had their vices.
*what does it mean to be a leader? *
Being a leader means defining and exhibiting moral and ethical courage and setting an example for everyone. •
A great leader posses a clear vision, is courageous, has integrity, honesty, humility and clear focus. He or she is a strategic planner and believes in teamwork.
Our great and humble knight 
conclusion
To err is human and all leaders are human, it would be wrong of us to expect leaders to be perfect we should try to copy the good and ignore the bad, a leader is just there to take you to your goal and he doesn't have to be perfect, what makes a leader is his followers and to be a great leader supportive and loyal followers are needed.