Any rope can fail if it has been damaged, or if it is cut over an edge. Rope damage can be caused by many factors, including, but not limited to, chemical contamination, dirt, exposure to heat, exposure to ultra-violet radiation and improper storage. It is up to each climber to make constant inspections of his or her rope to insure it is undamaged. Proper storage of your rope will prolong its life as well as yours. An accurate rope log can be of tremendous use when assessing the life of your rope.
Modern ropes are far superior to their predecessors, but if they are used improperly, they can fail.
They are not made to take forces over sharp edges. They can sustain damage without showing visual signs of that damage. It is the responsibility of the individual to know the appropriate use and limitations of the rope chosen. Any misunderstanding of the specifications and limitations of your equipment can lead to serious injury or death. From the wedging type of chock stones to the variety of camming devices, most cracks can now be utilized for protection, but much of the recent advancement in protection design falls into the category of small crack protection.