A Junior George is a person you work with who is a complete dumbass and shouldn't be working there or anywhere else in the same industry at that position. It is like hiring a security guard from kmart to guard the president, or George Bush Junior to be president.
Best used with "fucking" in the middle to add empasis (as below)
That asshole just fucked everything up on a task that was so fucking easy and fucking simple that he has to be a Junior Fucking George!
I can't work with these Junior Georges any fucking longer!