The following anti-patterns focus on the sprint planning: Oversized sprint backlog without objection: The team regularly accepts more issues into the sprint backlog than it can stomach without the scrum master’s invention. Invest upfront during the product backlog refinement, and you will keep it productive.
Scrum Master Anti-Patterns During the Sprint Planning. Over refinement. You can spot most of the Product Owner anti-patterns in the PO’s backyard — the Product Backlog and its refinement: Storage for ideas: The Product Owner is using the Product Backlog as a repository of ideas and requirements.

Another anti-pattern is having too many Product Backlog Items refined. The following article points at 28 Product Backlog anti-patterns — including the Product Backlog refinement process — that limit your Scrum Team’s success.

The purpose of Scrum’s sprint planning is to align the development team and the product owner. Product Backlog and Refinement Anti-Patterns. The following article points at 28 Product Backlog anti-patterns — including the Product Backlog refinement process — that limit your Scrum Team’s success. One of the dangers or anti-patterns of backlog refinement is to split work into “design sprints”, when stories are analysed and written, and “dev sprints”, when they are built. I sometimes call this – death by a 1000 questions. The team does not have enough refinement sessions, resulting in a low-quality backlog. Too many teams discuss stories in too much detail in one meeting or session. Anti-pattern: Too much discussion at one time. So, what are Sprint Planning anti-patterns of the Scrum Master, you may ask yourself? I can think of one Sprint Planning anti-pattern that falls into the responsibility of the Scrum Master: not ensuring that an important improvement issue from the previous Sprint Retrospective to help the Scrum Team improve continuously becomes a part of the Product Backlog. Both need to agree on the shippable product increment of the next sprint. The Purpose of the Sprint Planning . I’ll take the form of “anti-pattern” and then a complimentary “tactic” or more in describing ways to improve your backlog refinement.

Product Backlog Anti-Patterns of the Scrum Team.
Avoiding the following 19 sprint planning anti-patterns will help, too. The Product Backlog According to the Scrum Guide.