Sometimes I find people get really hung up on sprint boundaries and the intense focus to start and end things within a sprint. They want everything committed to at the beginning to be nicely completed at the end.
Academically this makes sense, but reality is different.
What happens when I finish all my work 2 days before the sprint ends? Do I fill the other 2 days with code reviews and tech debt work? Do I just wander off and take paid leave? (the answer is no)
I prefer to describe sprint boundaries as “mile markers along the side of the road.” You don’t stop and get gas at a mile marker, you get gas when you need gas, and when there’s a gas station available. But the mile markers are a scale you can measure progress against, and without measuring distance, there is no concept of pace or progress.
Instead, think about pipeline flow. If you need work, you pull from the backlog. Refinement should be continuously creating ready work, and the team should keep pulling it in.
Sprint boundaries are a moment to measure and reflect. Keep driving past them.