Product Backlog refinement is not a mandatory Scrum event. Why is this and what is Product Backlog refinement?
PBR is defined as an activity in the Scrum Guide and not as a mandatory Scrum event. Teams can choose to do PBR in a designated meeting, if that suits them. However, teams may find other good ways do PBR; for instance, I’ve seen teams do PBR everyday for about 15 minutes (timeboxed) after lunch or before the daily.
Backlog refinement is the activity of getting the top of the backlog into sprint-ready state. Refined backlog items typically have clear acceptance criteria and are small enough to comfortably fit in a sprint. Teams might have specific criteria for items being sprint-ready (e.g. INVEST) but the thing I’m looking for in refinements is constructive discussion with the aim of finding the smallest pieces of work that deliver the most value.
By not making it a mandatory event, the Scrum Team can find their own way in balancing focus on sprint execution and doing just enough “looking ahead”. A distinct event is not needed, hence not prescribed, keeping Scrum as empty as possible while staying true to inspection, adaptation and agile principles.