I guess that's why I use reflectors, as a fall back safety precaution, but more for an added effect. But I run with two sets of headlights and front flasher, plus 3 sets of rear lights, so if any one were to go dead I would still have the others. Obviously I know there are people who can't afford multiple lights but they can get adequate to be seen and to see with lighting for under $100 for both front and rear, combined with cheap reflective safety vest and other reflective gear they would be plenty safe. Some of these people who cry about the cost of lighting up a bike think nothing of it go buy coffee at Starbucks every day, or a 6 pack of beer every night, or a pack of cigs every day. Just sayin.