I had drum brake fail on me twenty years ago. One pad fell off the shoe and got stuck in the other shoe. It locked the wheel for 100 Yards. Thank god it was only the rear wheel of the motorcycle.

As for bicycles, my local rides definitely do not require disc brakes. But I spend a month in France every summer. There were descents where I had to stop because my hands have cramped up from squeezing the brakes so hard for so long. I would have given my left nut for a set of hydro discs!

My next road bike would have hydro disc. Am I going to buy it soon? No. But when I do buy it, it will definitely have disc.