"Communism won't work because I only work for selfish gain so everyone else must be the same as me. Anyone who says they'd work for non-selfish reasons must be lying because I'm selfish and everyone else must be just like me. And if they set up a society where selfishness wasn't the main motivator, I'd be out of there to go where I could still be selfish. Therefore communism is bullshit."

Communist societies have had their problems but this has never been a good argument.