Cooking.
Wrapping a present.
Growing food. Just can’t. Or I just don’t want to devote the time, idk. Flowers and other plants, no problem. But anything edible (besides the wild lemon mint in my yard or one cilantro plant every year) just fails. Everyone says, grow some zucchini in a pot! Easy! You’ll get tons! NOPE. I got ZERO. But I did get some squash vine borers. 
That’s why there are groceries…
Yes. Suffered by 2% of the population. Statically, I should only have to kill two of my opponents to lose. I’m thinking a tennis ball cannon from the shadows should do the trick.
I am a disaster at learning languages. I have been in Montreal for 58 years and, while I can speak French to some extent and can read it readily, I just cannot understand the spoken language. Everyone seems to learn it faster than me.
Sex. I’ve had a normal male sex drive forever, but premature ejaculation haunts me. Not all the time, but mostly. I’ve found a great partner, and if I were competent I probably would have gotten someone pregnant in my teens. Still, I’m disappointed in myself.
Most things. I can’t swim, so we can start there. I also don’t drive. If I had to do either, even after some good training and time to acclimatise, I’d still be shit at them.
Count me among those who can’t whistle. The only way I can do it is to purse my lips and breathe in rather than out. Even that is pretty iffy.
My other “Bless your little heart” thing is tying my shoes. I cannot do it in the grown up way, only bunny ears and I don’t do that very well. When I was in my late 20’s/early 30’s, I worked at a State Hospital.
One of our patients was a woman with dementia who basically functioned on the level of a 3 year old. This patient would frequently drop to a knee in front of me and, with a heavy sigh, retie my shoes properly. It was humbling.
Let me put it this way. When doling out brains and manual skills, nature forgot to put me in the line for manual skills. Then it decided to screw with me by making me bad at math, as well.
Anything musical, absolutely no ability 
So far as I could think of, singing would be the closest for me–I’m not sure I’m quite in the bottom 1%, though, I can at least tell when I’m out of tune, which is almost always. But definitely bottom decile.
I sure don’t have the manual skills. I’m very good at mental arithmetic, but past what’s taught in 5th grade or so I’m lost. Except statistics. I was nervous about having to take a statistics class in grad school, but ended up with a B+. My incompetence when it comes to manual skills made it necessary for me to go to college, which I really didn’t want to do.
Oh man, that’s me. I took two years of Spanish in Jr. High. I only made a D because Mrs. Garcia was very, very kind. I’ve made other attempts since then, but it never goes well. I picked my college major (fine arts) partly because it didn’t have a language requirement.
Oddly enough, I seem to pick up modern computer languages pretty quickly.
My wife is like yourself. I’m the opposite here. I’m terrible at going to bed at a particular time, and if left to my own devices I can still often sleep 12 hours straight. I can function on little sleep, and I can wake up on time, but it requires an alarm.
Wait, I’ve been tying the bunny ears my entire life. How do adults do it?
The thing that I probably perform worse than 99 randos is: Knowing when someone is trying to insult me and reacting as expected, at least that is what I have come to understand. I apparently just laugh and agree with them, then elaborate further on the behavior they’re talking about. A friend of mine in college once exclaimed “It’s no fun to rag on Scabpicker. He just joins in!”
I mean, if you’re not lying about me, how should I be insulted?
Speling.
I am absolutely terrible at sleeping. It’s been years and years since I got a solid 8-hour night of good sleep. I am also horrible at cooking.
I am not the bottom 1%, but this is something I never could improve on beyond my current level.
And I’ve bowled a lot over the years. As a teen I was in bowling league after bowling league - sometimes two leagues at once - and I could never learn to roll a nice hook.
I’ve tried as recently as last month and I still could not throw a nice ball despite repeated attempts/adjustments. I must be missing some fundamental mechanics aspect.
mmm
This is me too, though I can sometimes get to sleep in until 7 or so. I can always tell if I’m starting to get sick because I’ll wake up after 7.
This would be me too, and I can’t tell if you’ve misspelled spelling or not until the helpful redline came up.
When the “dress” meme went viral, I was completely bewildered by the “blue and black or white and gold?” debate, because I couldn’t for the life of me see it as anything but light blue and tan.
Professor Shoelace does a nice job explaining the “kiddie” vs “adult” version of the exact same shoe-tying knot, and also why your shoes keep getting untied.
I can follow written instructions pretty well, because I can go back and re-read them.
But I am hopeless at verbal directions. When someone gives me verbal directions to drive somewhere, literally all that I can remember afterwards is the last thing they said. So their directions invariably sound like: “Blah blah blah something something, and take a right and you’re there!”
At least today I can usually tell them to save their breath and instead just give me the address and I can use Google Maps. It’s when they tell me that Google Maps doesn’t work for some reason or it brings you to the wrong place that I have problems now, so in that case, I have to write the instructions down one step at a time.
Years ago—before Google Maps and Mapquest—I tried to get directions to a hotel in downtown Boston using the hotel’s recorded instructions when you called. I had to call 12 times…each time carefully writing down the next step. 
Likely related to this is my general inability to hear music lyrics. I love listening to music, but they always sound like they’re being sung in a foreign language…where at best I can pick out a word or two here and there.
But this is all small potatoes compared to my absolute worst skill, and that is being punctual. It’s probably due to a combination of procrastination, having no sense of time, and undiagnosed ADHD. I can make a flight or a train or an important meeting, but only with supreme effort. Dinner reservations or a doctor’s appointment? I’m usually running about 10 minutes late. And something more amorphous, like a party? I’m usually running about an hour late.
Dancing. The only two people I can think of being worse than me at dancing are Elon Musk and President Ineptstein, and those are surely not among the 99 randomly chosen. So dancing it is.
As long as the contest does not take place in Finland I’d add small talk. In Finland it would be a tie.
As long as the target does not dress in red in front of a green background you’ll be fine.