For all that everyone complains about captchas being hard to solve, I don’t think I’ve ever failed one. Sure, sometimes it’s ambiguous whether a given box contains part of a bicycle, but those things are designed with the expectation that some of the boxes will be ambiguous: In any where it’s ambiguous, you’ll pass by either clicking it or not.
Maybe you can tell me what this one is: IMG_2341.JPG - Google Drive
So the way to prove you are human is by completing the captcha wrongly? Makes sense, I am very human.
I read that too, but it is illogical. They know already what the answer is, otherwise they could not tell you that you have not passed the test. If they know the answer already there is no information gain in your input to train the bots. Nice story, but I don’t buy it.
One of the older styles presented two distorted words: one of them was already known and could be used to verify the answer, and the other was unknown (or less reliably known) and could be used to label their dataset.
V4X4
The training ones always have multiple pieces to them. The site already knows some of them (from other humans having already solved them) and is unsure about some others. It uses the ones it does already know to decide whether to let you in, and uses your answers to the ones it’s not sure about to add to its library of ones it knows. And of course, the user doesn’t know which ones it’s sure about in advance. It takes a bit to get it started, but then it becomes self-sustaining.
Years ago, I heard a lecture by Louis Von Ahn (founder of reCAPTHA) where he said they did exactly that. Basically, they observed that CAPTCHA was being defeated by scammers who hired huge numbers of people in Southeast Asia as Mechanical Turks. They decided to exploit the exploiters by extracting work out of them to train AI.
Hopefully we’re far enough into this FQ to share this:
There were several posts back in the day of a Roomba thoughfully smearing that surprise - no longer steaming - over the entire room of hardwood and carpet. I assume a fresh one would not trigger the collision bumper on the vacuum. I hope our computer overlords have learned to recognize a pile of shit when they see it now…
Eventually we are going to have to answer a bunch of questions about tortoises and husbands hanging nudie magazine photos on the wall to access a web site.
Oh, Lord, my ribs hurt! 
Only way to find out is to stand Elon in front of one of his self-driving cars
And what, pray tell, would count as passing the test? The self-driving car braking or running him over?
Some move out of the way and others embrace it as colleague.