Because, according to Brazilian physician Claudio Gil Araujo and Discover Magazine (which makes it absolutely, totally true, yo), being able to sit cross-legged on the floor and then stand up again without using your hands or putting your knee down, etc. is an excellent indication of how long you may live. At least if you're over 51 (and able-bodied enough to attempt it in the first place).
Why? Because having enough flexibility, balance and strength to sit on the floor without crashing on your ass, and to get up without needing your hands helps in avoiding falls (which get more problematic when our hips start snapping like Doritos), and means you're in good shape in general, which helps in avoiding death (which will never not be problematic). The test is scored out of ten with anything other than feet-only subtracting a point. Anyone with a score of less than 8 was twice as likely to die within the next six years. Anyone with a score of three or less was five times as likely to die. Which might raise someone's chances at death to only 5%, but still. Whoa.
I'm blessed enough to be able-bodied, but I found to my chagrin that I needed to use one hand to get up. Nothing like having my delusions of physical prowess sunk like the Titanic in literally one sitting.
My physio therapist (Apparently sitting in terrible positions for 5+ hours a day typing for over ten years causes repetitive strain injuries. Who knew?), who is in his (very) early 30s and looks like Captain America, can of course get on and off the floor using only one leg. Which would be intimidating if he wasn't so adorable.
So, my current exercise regimen now includes simply getting off the floor without using my hands. I managed it once today! Once! ONE WHOLE TIME!
I'm going to be immortal. Seriously.