If one comes off the M50, as most people going to Dublin Airport from the country do, one sees a vague sign saying "toll ahead." When one gets closer to it, one discovers there is a way of paying without having to look for change, but at that stage one is in whichever queue one happens to get into because nobody gave the information one needed beforehand. Nobody on the whole M50 thought of telling anybody anything, confirming my view that my profession of engineering is very taken with large constructs but not very good at thinking of the people who have to use them.