When acting in the role of Scrum Master, whether in my own team or when offering advice to others, there is one question that I find more pertinent than any other when troubleshooting a problem or concern, especially with teams that are inexperienced in lean or agile processes.
How much value did the team deliver last Sprint?
In a nutshell, that question encapsulates everything that truly matters. What “value” means, or how it is measured is an exercise for individual teams, but the principle of needing to know it is a universal truth.
Every team exists to provide value. That might be value to the user, to the business, or to something/someone else, but somebody needs to tangibly benefit from the team’s work. We do not exist to write code, nor to deploy 100 times a day, nor to ‘be agile’. Our users simply aren't concerned about any of that stuff, and neither should they be.
If a team — or at the very least their Product Owner — does not know how much value they have delivered, or at least anticipate to have delivered, how can they ever know that they are working on the right thing, or that there isn’t a ‘better’ selection of PBIs that the team could have done instead? The same is of course equally true with future Sprints, and Product Backlog Items in general.
It may be impossible to know for sure how much value an item (or items) may deliver, but that does not prevent an estimate being made. An estimate doesn’t have to be perfect. It could be a relative measure similar to a ‘Story Point’, a dollar amount, even a time saving compared to a legacy system. Anything that suits the product landscape and provides the team with the information that they require.
Only when a team can quantify what it is delivering (in this context velocity is irrelevant) can it transparently and openly inspect and adapt. If a team halved its velocity but in doing so quadrupled the value being delivered, that’s probably a good thing, but the team can only draw that conclusion if it can quantify value.
Effort and value also go hand in hand: if the cost of developing an item is far greater than the return it will provide then there is a high probability that the Product Owner (or customer, in some contexts) would choose to invest efforts elsewhere, where ROI is greater. Value is fundamental to a team's decision making and their ability to satisfy their customers and stakeholders.