Minecraft wiki entry for Endless_circling_pool, associated text: This is why many players build an endless circling pool when they have to be away from the computer. An endless circling pool automatically moves the player continuously. However, it can malfunction once in a while, causing the player to stop moving. Because of this, make sure to check your computer every 15 minutes (or however long the player is allowed to be idle before they get kicked off on that specific server). Also, note that some servers ban the usage of endless circling pools.