A person employed by an agency to work alongside someone who has been doing the same job for years, and the fuckwit will not take any advice from the experienced worker
Used in similar circumstances as dumbass or dipshit. Fuckwit is reserved for someone who is so bafflingly stupid that the other two words just don't do the job.
A fuckwit is a dumbass person who fucks with your life, for example, if you shit on people, you are a fuckwit, if you listen to mumble rap, you are a fuckwit, if your IQ level is low, you are a fuckwit. If you piss on people, you are a fuckwit.