Anyone who tries to log in as an administrator gets automatically blocked, which I then make permanent ASAP. Currently, this includes a crap ton of Italian IPs from static.albacom.net and fastwebnet.it hosting. US would-be hackers mostly come from biz.bhn.net. I block all traffic from China, and most coming from Russia and Eastern Europe. If you’re throttled, you’ll likely be permanently banned.
Basically, if you make a nuisance of yourself, you’re banned. Whether or not the ban is permanent is decided by what kind and how much of a nuisance I think you are.