This is a good characteristic but it has to be very balanced. Too much, then the leader becomes unfair, harsh and the team members dread work or being around their leader which inhibits the team's performance. Then being too lenient will make the team lose respect for the leader and the leader won't be able to address problems very well. Discipline should be there to establish and maintain a strong foundation of organisation and morality.

Obviously there has to be some form of discipline, when it is necessary. There has to be a balance so as not to be unfair or to lenient.

Only as a last resort.