Some people had to jump again because they were not successful on their first attempt.
But some competitors did not jump off the rope to complete the obstacle. They used their feet to land on the platform. But if a competitor had to swing again they are in danger of touching the water and within the first seasons, it took out a bunch of people and eventually in season 3, it was replaced by the Log Grip.
American Ninja Warrior 6 Version
This was only used in ANW 6 in the St. Louis Qualifying. This consisted of A trampoline, 2 shortened ropes, and a cargo net. They had to jump from a trampoline to get to 2 shortened ropes, and then they must swing from the 2nd rope onto a cargo net, from there they must climb down the cargo net in hopes not to touch the water below. From there they go under to get to a platform which will take them to the next obstacle. This proved particularly easy as few failed this version, either missing the rope or not getting a good grip onto the net. The Rope Swing was a fusion of the Jump Hang and the Rope Junction.
• This Rope Swing was used in Happy Wheels games.