It is the only "superfiber" that does not break if bent or folded. The relative flex life of UHMWPE is 100 versus only 8 for Aramid fibers. This means performance remains the same no matter how many time the hand is flexed or fingers bend. All day performance.
Aramid fiber is more brittle than UHMWPE. Its flex life performance is 12 times worse than UHMWPE. As the hand is flexed and fingers bent the fiber cracks and breaks. Over time with each bending motion it looses its strength. Kevlar factories are covered in a "gold" dust because of this.