Hackers seem constantly to be brute force attacking your site by guessing your username and password. WordPress usernames can be easily found indeed. If it is found, it makes hackers’ life easier and they start guessing your password. Attackers can use a took to guess your username or simply entering a URL such as the following:
I have been very successful protecting my WordPress sites by hiding WordPress usernames. This WordPress video tutorial explains how to hide/disguise your usernames from hackers and to further improve the security of your WordPress site and blogs.