Why is the PIN of the bank card only 6 digits?

  The password of the bank card is 6 digits, and the password of the third-party payment is also, but when we go to register the accounts of many websites, we are required to use complex combinations of letters, numbers and special symbols. The latter situation is often a headache because we can easily forget passwords that are too complex.
  Why is the password related to money so simple, while the password for the website registration account is so complicated? Is money more important than other things? Obviously not.
  This is a question of economics, and any innovation must consider the economics of consumer use – to reduce their energy consumption, or to help them save money.
  It is undoubtedly economical to use a 6-digit PIN for bank cards. First of all, bank cards have a wide range of users. For example, elderly users may have poor memory, and young people who sign up for websites and mobile software accounts at ordinary times have a lot of passwords. If the password is too complicated, it is very likely that Get the passwords all mixed up. A 6-digit password is much better, easier to remember and less confusing.
  The same goes for payment passwords. An engineer of the payment tool of a large Internet company once told me that when they designed the payment password of the payment tool, they also considered complicated methods, but finally decided to use the simplest 6-digit password. After they passed many simulation experiments and tried many models, they still found that 6-bit passwords can best achieve a balance between security and economy.
  In fact, one more thing should not be forgotten, whether banks or third-party payment tools of large Internet companies, they all have strong technical strength, have strong security systems based on data, images and other technical means, and maintain the industry with high salaries. The best team of engineers in China can completely resist the attacks of ordinary hackers and ensure that the user’s password security is not a big problem. Therefore, there is nothing wrong with a simple 6-digit password, which brings economic benefits to consumers.
  On the contrary, the reason why the account registration of many websites needs more complex passwords is because they are not strong enough, and they must ensure security by making users spend more energy and remember more complex passwords. An interesting phenomenon is that the weaker the company’s website or mobile software, the more complex the password you need to remember.
  Considering the economics of user use, another example is the case of why supersonic aircraft fell.
  At present, the civil aviation aircraft that humans take are mainly subsonic. The speed of sound in the air is generally 340m/s, while the speed of civil aircraft is generally 250m/s. Why not use supersonic aircraft? In the middle of the last century, engineers in Europe and the United States could already design supersonic fighter jets. If this technology is applied to civil aviation and shortens the time of business travel, wouldn’t it greatly promote the progress of global commerce and trade?
  Europeans do exactly that. In the 1960s, the French and the British united to create a Concorde that was destined to leave a strong mark in aviation history. The Concorde can fly at twice the speed of sound. Taking this plane, the time from London and Paris to New York , which is shortened by half compared to taking an ordinary civil airliner. Before, it took six or seven hours to get from Paris to New York, while the Concorde took just over three hours.
  However, the Concorde has now basically withdrawn from the civil aviation market, and the UK and France have produced about 20 aircraft in total. In addition, the Soviet Union also developed a supersonic Tu-144 civil airliner, which first flew in 1968, but has also withdrawn from the market now.
  Why supersonic airliners can’t do subsonic airliners? The most important reason is undoubtedly that users feel a lack of economy when using it. In addition to the environmental problems of noise pollution and the uncertainty of safety brought about by supersonic speed, the most important thing is that the fare is too expensive (mainly due to high fuel consumption and high maintenance costs), which is two of the ordinary civil aviation fares. This makes it abandon the large market for middle-class business people and ordinary people, which are just the basics for civil aviation aircraft to maintain profitability.
  A good product does not need to rely on more complex and front-end technologies. It just makes it economical for users to use it, and it is visible to the naked eye.