Sprint planning is the meeting at the start of every sprint where a team decides what to build in the next one to two weeks. It's a core agile ritual, and what the team commits to here is what actually gets shipped.
The typical flow: the product manager walks through the prioritized backlog, the team estimates effort (usually in story points), and together you decide how much fits based on the team's velocity, the average story points completed per sprint.
The common mistake
Sprint planning gets treated as a scheduling exercise instead of a product decision. You're not filling capacity. You're deciding what matters right now. The best planning meetings happen when the PM comes in with a clear "why" for each top item. Not "this has been in the backlog for three sprints" but "three enterprise customers asked for this last month and we're losing deals because of it."
Keep it realistic
Optimism in sprint planning creates burnout and broken commitments. Commit to six things and ship six things rather than committing to ten and shipping seven.
If your product roadmap is connected to real customer feedback, sprint planning stops being a guessing game and becomes a focused conversation about what's most valuable right now.