Rope Snaps during launch big ship launch

During the ship launch of Scot Explorer at the Royal Rodewes shipyard in Hoogezand, The Netherlands, a line at the stern of the ship snaps. Then, the hull collided several times with the concrete quay wall. Both the paint and the quay wall were visibly damaged.
This happened either because the rope was old and quite worn, or the force needed to support this ship was not calculated correctly.