This is a small note about fakap and professional impotence of the site with hundreds of millions of users, or "How not to make a captcha?"
There is no need to go far for examples of normal captcha: this is the famous
reCAPTCHA :

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...
and the Cyrillic captcha from Yandex :

But today we will talk about the
Chinese captcha in its worst form. And
it's not in hieroglyphs .
Here is the captcha of the Chinese Railways website (local monopoly) at
12306.com . She asks to mark a picture (or pictures) with the image of
agate (玛瑙).

Do you know the correct answer?
This is not only the second bottom picture with a red bracelet, but the first one too. And do not blame Habrastorage or me for pinching a picture, this is its
original quality and size .
Yes, do not know whose certificate on the site where you are going to leave your passport data, telephone number and payment details, this is the norm:

A few words about the significance of the site
12306 for China. This is the
only way to buy train tickets via the Internet . Any existing intermediaries (qunar.com, ctrip.com, alitrip.com) only have a staff of
bio-bots of employees who sit in a stuffy office and buy tickets on the official website in the same way. By the way, here he is:
In the screenshot, a captcha asks you to find a poster or a poster (or maybe several).The site is used by hundreds of millions of people, especially in the period of the Chinese New Year, when the entire poor one and a half billion people move to different parts of the country to meet the year with their relatives.
Something like this.Here are some more epic examples from a site that has to cope with millions of visitors daily and be user friendly even for people far from computers.
Select pictures with ants and
wonton :

Answer2, 6 and 8 (in order, from left to right, top to bottom)
Select all
cards :

Answer1, 3, 4, 7 and 8 (think that 4 and 8 - seal !)
Find a
fridge :

AnswerOf course it's number 5
Find
aquariums :

Find phone booths:

Of course, using the exception method, you can try to guess what the computer means. But according to statistics, only 8% of site visitors pass this captcha the first time. And to change it, apparently, is not planned.
This is not the first and, it seems, not the last joint of one of the most important portals for the Chinese. Recently, they began to block resellers tickets by IP-addresses, sending thousands of innocent clients to the bank. Less than a month ago, the site introduced a two-step authorization, the SMS from which did not arrive for hours. And during peak hours, they were denied the server, paralyzing the purchase of tickets throughout the country for the whole day.
If someday you see an inconvenient captcha, then remember that in the absence of competition, with public funding, a site with a multimillion audience may be so.