When I first came to America I bought an airline ticket out of New York because it was so cheap. Turned out I had incorrectly agreed to go to Dulles, not Dallas.
That's when I learned to call it DFW.
Perhaps I shouldn't mention the time I headed for the wrong airport only to be told of my mistake at which point I found the right airport and made an approach to the wrong runway!
That's when I learned to back the approach up with the ILS.
I'd say it's surprisingly easy to get it wrong.