Yes, to make sure they are correct. Once that is established, they are first priority.

Well, not always. In some circumstances, requirements can be changed for the convenience of the company.

But not in healthcare, communications, transportation, defense, finance, generating/managing electricity, ....

So, pardon my tunnel vision--I've been full-time in at least one of those since 1974. (But only doing software since 1985).

Except for twenty months finding out that teaching, much as I enjoyed it, doesn't pay the bills. And now that I no longer have the bills, I'm too old to switch. But that's off-topic.