>It's also very safe to try out and do, which is counterintuitive to most people who haven't tried. Overwhelmingly the most common failure mode on a unicycle is that you just stop riding it, and then it either gets ahead of you or behind you, and you hop onto the ground.

Ha. My experience with a unicycle was the exact same as my experience with Segway and Hoverboard: flat on my back, knocked-out cold, with back-sprain that lasted months.