I was recently asked an uncomfortable question: “I already gave you this information, why are we meeting again?” Ouch. The truth hurts. I had made a mistake. Hint: my mistake is the last item in this list. TL;DR: When inviting people to cooperate on a task, make sure you invite everybody who is involved.
Different communities sometimes disagree on things. If you only meet with some folks, then you might get answers that other folks aren’t on board with. You’ll think everything is okay, until they hear about it, and then you’ll find out you’ve stepped on a trap.
Different communities sometimes have friction with each other. This might not have anything to do with what you’re doing, so you might not know. Putting them in front of each other can bring up topics and issues that are bigger than just your project. You might want to know about this context early on, before you get too far into what you’re doing. It could end up being relevant.
Sometimes communities are hiding from each other, and want you to serve as a go-between them. That’s probably not your job. If you serve as the diplomat, then you’ve taken on an additional new role. Communicating between teams is a whole job, all by itself. Do you really want that additional burden?
Hearing multiple communities talk about the same things is one of the best ways to dig up differences in terminology. Domain Driven Design teaches us to always be on the hunt for a single “ubiquitous language”. Having everyone talk to each other really helps shine a light on differences in language. Can you get everyone to agree on a single definition for each term?
If you make progress without one group on board, then you run the risk of finding out later that you missed something. Even if nobody disagrees exactly, just not being involved might cause confusion and follow-up questions. It can feel like disagreement, even if it’s just clarification. Some of your work might have to be re-done or started over. People have to feel confident in what’s been done. Not being included does not make people feel comfortable.
John DeHope 