We all make mistakes. Even CW DXers. But some operators do very unhelpful things on purpose. They are DX Dicks.
Suppose you hear a rare station. What a pileup! You need him for an ATNO! What do you do?
You do not tune up your amplifier without QSYing! If you do, you are being a dick.
You do not put your keyer in a loop to call continuously. If you do, you are making it harder for the DX operator to copy the station he wants to work and harder for the other callers to figure out where he is listening. You are being a dick.
When the DX calls another station or gives a partial call that is not part of your call, keep quiet. Otherwise, you are a dick. This is probably the most popular way to be a dick, especially in Europe. Don't do it!
If you are lucky enough to hear the guy the DX is working, you do not try to overpower him so the DX station doesn’t get his acknowledgement. Doing this makes you an especially rotten dick.
If someone accidentally calls on top of the DX who is working split, you do not send UP UP UP UP UP UP or IDIOT or GM or HI or LSN or anything at all on the DX frequency. He will figure it out. I know you may think you are helping, but you aren’t. In fact, if you do this you are certainly being a dick.
If a whole collection of dicks are insulting each other on the DX frequency, do not join them and become a dick yourself.
In fact, read and follow the DX Code of Conduct and you will never be a DX dick!