The digital signage in the KRail Airport Express caught my eye. See how the
- stations are grouped together to express physical distance
- green dots turn red to show progress
- dot underneath the next station blinks at a steady pace
Incheon is close to an hour away from central Seoul, which is comparable (comparably bad!) to Narita and central Tokyo. Having proper signage to make it dead simple to know when your stop is coming up makes it a little easier to bear.
On the train to the airport, there was even a panel that shows flight information. I imagine the column on the right is to indicate whether flights are delayed or not.