Why is SMS CAPTCHA not humanized?

Kotlin
IOS
VB.Net
SQL
Node.js
Swift
Ruby
Go
Oracle
Git
Laravel
Mongodb
Asp.Net
More...

I found that the mobile phone CAPTCHA sent when registering on the Internet is usually a 4-digit, 6-digit pure digital verification. But this kind of user experience is not good, if it is very long and easy to type wrong, it is usually a random number between 1111 and 999999. Why not design it into three. Or a number that is easier to enter with a hyphen?

CAPTCHA python

Mar.05,2021

this is also an indirect default standard, too little (too little is possible to try to get the right number), too much is not good, 4-6 is the best, 6-digit is the best, you see Alipay, WeChat Pay 6-digit, bank card password 6-digit

Previous: Is there a way to convert url to base64 coding?

Next: The picture uploaded by ueditor cannot be displayed.

False
Django, Why does the system automatically generate an empty session? every time the request is made?
Use python to convert dict1 to dict2, in the example. I tried for a long time but couldn't find a solution.
How to self-start the php-fpm service when building a LNMP environment with docker?
Can an array in react state be bound to a dom state using an element in the array?
Wechat browser version 6.6.5 cannot prevent the springback of pull-up and drop-down to the top under ios system.
In express+hbs, how do you define the routed data as a variable on the page?
How to use symbol reference of Iconfont in dva
How to elegantly add data to JSON objects?
Using node to build video streaming server
The proportional width of the echarts graph is inconsistent.
React uses axios to call the background data. After success, how to jump to the page based on the returned value?
I don't understand what a linux command means. Please explain it.
Vue introduces multiple components in vue-router by nesting named views, and does not refresh the same reference in other pages.
Running nodejs reports fewer errors ")"

A question of SQL statement injected by SQL
The upload file in element fails to be uploaded after it is uploaded to the server. How to close the uploaded file manually?
The webpack configuration file uses the variables in the configuration
A question about the interruption when JAVA uses Condition?
How to push all the historical commit of the git project to the new warehouse