Charisma is something one has. A person can exude charisma without speaking a word.
Persuasion is something one does. Having persuasion means getting them to want to do things on their own and take ownership over an idea.
These skills are important in a business communication so owners can motivate employees through the difficult periods and to help them stay centered through the good times.
Martin Luther King, Jr. and Barack Obama are very charismatic. They inspire and encourage people to make a change in the world. Their charisma gathered people together to make a difference.