So, looks like #archlinux enabled pam_faillock by default, with default options so if you fail to input password 3 times in 15 minutes (in login, screen unlock or sudo), you are locked out for ten (10) minutes !!

Quite extreme, for people like me that have multiple devices with different password that can be connected to same keyboard, which leads to input wrong password at first (even second) try from time to time; add to this that I lock the screen quite often and you get a quite annoying picture..

If you are like me and you don't want to disable this because can be useful, but mostly because you don't want to fiddle with pam config file, you can edit /etc/security/faillock.conf and set more sane settings. (thanks to this forum thread)

If you get locked out, but you have root access, you can reset the lock with

# faillock --user yourusername --reset