Passwordless Authentication involves using two factors: knowledge and possession. The former can be easily shared, misused, or stolen. The latter cannot be shared, and it is harder for hackers to gain access to the information. The latter can include a phone number, email address, FIDO authentication, RSA key, or push notifications. The disadvantage is that knowledge factors are easy to hack. A strong passwordless solution should never require the user to memorize the password or the public key.
The next factor is the biometric factor. It could be a voiceprint or iris scan. It is difficult to replicate, and it can also be difficult to forget. A biometric factor can be used to gain access to sensitive material without the need to enter the password. This method also has an advantage when it comes to improving the customer experience. It will make the user experience much better.