I've personally chosen a strategy to work around scope that is heavily reliant on incremental delivery. Instead of asking how long it takes to deliver something, I guide people into asking if we could do something smaller first. It has lead my team into doing weekly, even daily releases where each release delivers some value without taking out that was already there. Always turning the discussion towards value in production, and smallest possible increment of that value has been helpful. It enables movement within the team. It enables reprioritization. And it enables the fact that no one needs to escalate things to find a faster route to get the same thing done, the faster route is always a default.
We work a lot with the idea of being customer-oriented - even obsessed, if that wasn't such a negative word. We are thinking a lot in terms of value, empathy and caring, and seeking ways to care more directly. We don't have a product owner but a group of smart minds both inside the team but also outside supporting the team with business intel. The work we all do is supposed to turn into value at customers hands. Production first helps us prioritize. Value in production, value to production.
We didn't always deliver this way or work this way. We built the way we work in this team in the last 2.5 years I've had the pleasure of enjoying the company of my brilliant team.
Looking at things from this perspective, I find there is a message I keep on repeating:
Scope does not creep, understanding grows. Repeat until folks get the nature of software development and stop fighting.— Maaret Pyhäjärvi (@maaretp) November 9, 2018
If you have a product owner (or product management organization) and they ask you to deliver a feature that customers are asking, they don't know everything but they do their best in understanding what that would be like. They define the scope in terms of value with the customer.
If they ask you to estimate how much work there is to do that, you need to have some idea of the scope. Odds are, your idea of the scope isn't same as theirs, and theirs is incomplete to begin with. The bigger the thing asked, the more the work unfolds as we are doing it.
They asked you for value 10. You thought it will take you effort 10. That is already two ways of defining the scope.
In delivery, you need to understand what the value expected really is. Often it is more in terms of effort that you first guessed.
Telling folks stuff like "you did not say the buttons needed to be rounded, like all the other buttons" or "the functionality is there, but the users just won't find it" may be that it works as specified but not as really expected. I find that those trying to specify and pass the spec do worse than those trying to learn, collaborate and deliver incrementally.
Scoping is a relationship, not something that is given to me. We discover features and value in collaboration, and delivering incrementally helps keep the discussion concrete. Understanding grows at every step of the way, and we should appreciate that.
** note: "Scope does not creep, understanding grows" is an insight I have learned from Jeff Patton. There are many things I know where I picked them up, while there's more where I can no longer pinpoint where the great way of describing my belief systems came from. I'm smiling wryly at the idea of mentioning the source every time I say this in office - we're counting hundreds.