Why do brake levers have those knobs on the end? Just as the one-eyed bike mechanic.
I was working on a customer's bike, at the shop, and had it hanging on the repair stand, as usual. I replaced the brake cables and adjusted the tension, cut the cables to length, and then turned to adjusting the rear derailleur. I hadn't capped the brake cables with those little crimp-on cable-ends, yet, but I figured I'd do it when I got through with the derailleur.
"Hey, Jon, look at this!"
I turned to look, and the end of the rear brake cable skittered across the lens of my glasses and stabbed me in the cheek. Blood flowed fairly freely, as I jumped back, startled and confused.
Man, that hurt!
That was when I started making it a rule to cap those stupid cables as soon as I trimmed them.