Sometimes, in the middle of a coffee break, conference delegates turn to interpreters and ask: “how do you say this or that in English (or any other language)?” If what they want to know is related to the topic of the conference and is not out of context, the interpreter may be able to answer straight away. But often the “this or that” relates to something completely different or is totally out of context and delegates are then very disappointed not to get an immediate and straightforward answer.
No human brain is powerful enough to know ALL the words in the world in all fields and contexts. Actually, no computer is powerful enough either. There is no super giant IT database of words in all languages covering all the possible topics that exist.
This is why, interpreters need to prepare well before every conference,to make sure they know as much as they can about the topic and the kind of terminology and language used in the different languages of the conference.