I've shared the story before of commuting by bike to work one early morning and nearly clocking a guy on another bike who was riding the wrong way, wearing dark clothing, and had no lights or reflectors. Literally the cherry on his cigarette is what kept me from nailing him at high speed.
See? Smoking saves lives.
I've nearly left hooked one, and only knew it even happened because I heard his freewheel buzz at the last second. (Nice quiet freehubs save lives too.) Even then, after turning around to see what the hell that was, I could barely pick him out on a primer gray bike with no reflectors, wearing a gray sweatshirt and jeans. My headlight (though it claims 8,000 lumens, I've tested it alongside some reputable brands and I'd put it around 500 on low, reasonably comparable to the 700 a car low beam should be producing, which is where I normally run it) was barely enough to give him some contrast against the old asphalt. For comparison, I can generally see a car's taillight reflectors faintly at a half mile, or quite clearly at about a third of a mile with that same light.
People like him are the reason I keep red, yellow and white reflective tape around the shop and tend to slip bits of it onto any bikes with no reflectors during repairs. Either disguised in a similar colored area of paint or in places where it'll be a PITA to peel off. Even a 1" square of it in the right place is surprisingly visible at night.
FWIW, if anyone wants a
GUEE Sol 200 (without the useless clock, and I disagree with their "unclear" assessment of the low battery warning: the ring around the switch lights up yellow at least 20 minutes before it dies in normal mode) for $22 plus shipping, (should fit a Flat Rate Small fine, so $7.20) let me know. Our vendor got stuck with a case or two when they were discontinued, so I'm passing on the savings in hopes of getting more lights on bikes. USB rechargeable, compact, 3+ hours on normal setting, and plenty bright to be a good backup plan or a primary commute light if your commute tends to stay under 15mph on dark streets. Also has slow and fast strobe modes if you want an attention getter for daylight riding. I've already grabbed one as my backup, and didn't get too nervous doing 28mph downhill a couple nights ago while trying it out though I'd recommend more light if one makes a habit of such speeds.
OTOH, have you ever seen a pristine traffic cone or barrel in the wild? There's just not enough light, reflectives and bright colors to get someone's attention when they're focused on their phone screen. Hell, we had a fire truck (complete with the big yellow and black chevrons down the back) rear ended a couple weeks ago in full daylight when it slowed to turn left.
