sentences:  However, this type of construction means that, during the bending process, the inner radius compresses and the outer radius stretches as the cable core moves.Initially, this works quite well, because the elasticity of the material is still sufficient, but material fatigue can set in and cause permanent deformations.The cores move and begin to make their own compressing and stretching zones, which can lead to a “corkscrew” shape, and ultimately, core rupture.