This is the only sensible reason I've read so far, from a comment in that thread: "There are behavioral biometrics solutions where profiles are built based on

This is the only sensible reason I've read so far, from a comment in that thread: "There are behavioral biometrics solutions where profiles are built based on keystroke dynamics etc. which allow with a high degree of certainty to identify if a user that enters the credentials is indeed the user we expect. Credentials are true or false. If somebody has your credentials he is able to authenticate. This is why i would like to know if the person who is entering the correct credentials is indeed the person that we expect to know them. Username and password have to be entered every time during the login process so those fields are pretty interesting to check if such a solution is deployed at the organisation. This is not possible if somebody copy/pastes their password." Nevertheless, I strongly feel that this is not reason enough to disable paste.