Complex sentence: Consequently, it is almost completely ineffective for angled and left-turn collisions; and it may cause a motorist to lose control of his or her vehicle in the event of an impending head-on collision.
Split into simpler sentences: Consequently, it is almost completely ineffective for angled and left-turn collisions. It may even cause a motorist to lose control of the vehicle in the event of an impending head-on collision.