The rotation system is a WUKF trademark. There is a coach who calls for change. There is a time of at least 15 seconds in which the fighters need to fight before they can change, and the coach who calls first, has the right to change. They can't change at the same time. It's also a strategy. There also needs to be a 6 points difference , to end the match sooner that time does. Plus, all three need to fight, if the score did not end the match sooner than time did. If not, the team is disqualified. Hope I explained it well.