If the “lay” of the rope (the orientation of the constituent strands, the “twist” of a rope) is in one direction, the rope can twist on itself as it stretches and relaxes. Underfoot, this could be hazardous to disastrous in a tightrope. One solution is for the rope core to be made of steel cable, laid in the opposite direction to the outer layers, so that twisting forces balance each other out.