Count failures over what time period?

Just to make sure I have my head wrapped around this correctly…

If I want more of an extreme aggressive setup…do I want this set to the least amount of time, 5 minutes, or the max amount of time of 1 day?

I have it set to 3 wrong login attempts or 3 wrong password resets as I am the only one generally accessing my site and I use roboform to autofill logins so I dont really have a need for wrong attempts myself.

Thanks