Your three-second password retry delay is far more likely to annoy users than preventing a brute-force attack.

If you insist on a retry delay, let the user enter a password five times without any delay. This would make no difference in the grand scheme, the trillions of retries needed for a brute-force attack, and guessing a password takes longer than three seconds of thinking anyway.

Another alternative is a tenth of the password retry delay but one added character. One added character slows down a brute-force attack by at least sixty-two (62) times, so one more character but a tenth of the password retry delay would still mean more than six (6) times the protection against brute-forcing.

On Linux, the password retry delay can thankfully be reduced by changing a value inside /etc/pam.d/common-auth or /etc/pam.d/login (out of scope for this post, you can search online for more details).