Back to the nasty question - what sort of Information System shall will we build?

"What sort of system do you want?"
"hmmm, one that processes all our customer orders, I think. What do you think, George?"
"Well Fred, I suppose so, but I know it has to be fast, and run 24/7."
"OK.........(???)"

We already know the problem with asking people what they want, but it is even worse than you think, because it's an open-ended question; and the problem with open-ended requirements questions is determining when the question has been fully answered. How do you know you have all the requirements? Well, you don't.

Wait, it gets worse! How do you know if the requirements you did get are relevant? If any of them are duplicates? If any of them contradict other requirements? Again, you don't.

So you need a different question. When you ask people what they want, you can get blank stares in return... but, if you ask people what they do, you will get all their knowledge and expertise in return; and that is where the requirements will come from... look for part 2 on getting to FRs soon.