It is true that we need to work at speaking and writing as clearly as possible when trying to communicate with others. I’ve found this to be the most difficult when you are crossing cultures and the paradigms are different.
I’m not so sure that Ed Koch was talking about cross culture communications, more so—What’s the matter with your hearing! [Not so much as a question, but as a statement.] What don’t you understand about what I’m saying? As only a New Yorker could of course say it.