The Problem With Requirements

Requirements documents are halfway between a peace treaty and a Christmas list.

Photo by Arisa Chattasa on Unsplash

I have an email from Glenn. He needs to get a piece of software built and wants to know if I can make it for him. At the end of his email, he says, “I’ve gathered all the requirements,” and offers to send them over.

He says it so confidently: “I’ve gathered all the requirements,” as if they were strewn across the ground and he just picked them up. The phrase sticks with me because I have no idea what to expect. Will it be a Word document, an Excel sheet, a PowerPoint, a mind-map, a set of Jira tickets, or Trello cards? Maybe “all the requirements” will be high-level business priorities (“The system will allow us to take payments”) or maybe they will be low-level descriptions of how to integrate with specific payment APIs. They might cover non-functional requirements (“it will be secure”). Will there be user stories? Wireframes? Designs? Or will he just say “design is required.” All of the requirements is such a bold claim. No edge case left unturned, no feature left behind. I can’t tell if Glenn’s confidence is that of someone who knows more than me or less.

People talk so confidently about requirements that for a long time I thought there was a concrete definition that had been kept secret from me. Perhaps a secret Business Analyst code, that details precise standards to follow. Maybe there’s an ISO standard for them. But every time I start a new project with a new person, out comes their own idiosyncratic way of documenting requirements and we meander through to a finished product. I’ve accepted that, but, I still find it weird that we pretend there’s a shared concept of “requirements” when there are so many options; scaled by T-Shirt sizes or Fibonacci sequences or SCRUM poker cards, prioritized with high, medium, low or MoSCoW (Must do, Should do, Could do, Won’t do). I find MoSCoW the strangest. The difference between “Must” and “Should” is subtle. “Could” is making a rod for your own back. And don’t even get me started on won’t. “Won’t run on Windows 95”, “Won’t be written in FORTRAN”, “Won’t cause the downfall of capitalism.” I’m always surprised this section isn’t longer.

Requirements serve a different function, depending on where you are in the software…