I've got a script that retries on a failed FTP connection, and at one point it was retrying on a failed login due to incorrect password (it retried the same password). It now detects password failures and doesn't retry. The remote machine instantly locked out the account under these circumstances. I can't see this script being much use, besides it also being trivial. You have to know the username, for a start.

Not worthy even of an acolyte. Try doing a script that detects disconnections and retries, that would be more useful, or one that transposes the case of a user-supplied login & password and tries that, in case the user got Caps Lock turned on by mistake.