Rotation is the process of changing your map position to another are of the map for a certain goal. This is mainly done to accomplish map objectives. It is important to know when you need to stop what you’re doing and go do something else on the map.
You’re defending your lane from a small push of minions on Cursed Hollow and a Tribute pops up. It is important to not only stop immediately and move to the tribute but move with your team if possible. Important objectives like these require key rotations in order to capture them.
You’re working on pushing top lane in the Dragonshire map and the shrines become active. Do you rotate to the top shrine or head to mid to channel on the dragon knight? It depends on where your team is. You have to make calls like these ahead of time and react fast when you need to. If no one is in the middle lane then you need to go there or tell someone else to while you cap the northern shrine.
Effective rotation is key to winning in all of the maps. If you delay movement towards an objective even by mere moments it came mean the difference in a loss or a win for the fight.
Watch for objectives that pop up and pay attention to what your team is telling you to do.