http://www.slate.com/articles/arts/television/2015/07/american_ninja_warrior_on_nbc_just_bested_bachelorette_in_the_ratings_what.html

I have spent the last couple of days imagining scenarios in which one might need to scurry across slanted boards that are staggered like a jack-o’-lantern’s teeth. Maybe it’s good practice for trying to cross a stream without getting wet. What about swinging from a piece of fabric to a rope? If your apartment building was on fire, perhaps this could be an exit strategy of last resort, curtains to cable line. How about running across a rapidly tilting surface? Useful for earthquake preparedness. Why would you ever need to climb over a wall that, at its very top, bends toward you? You never know when you will be summarily imprisoned by nefarious architects. As for why you would have to climb a ladder that is, essentially, one rung, requiring you to do a pull up that simultaneously raises the bar you are pulling up on, well, there is only one reason you would ever do that: You are on American Ninja Warrior.