Agile

One mistake that management force the teams to do… “FREEZE” their sprint backlog

One mistake that management force the teams to do… “FREEZE” their sprint backlog

Yes, one mistake that management force the team to do is FREEZE their sprint backlog, while the sprint backlog is the development team’s plan to achieve the sprint goal, it is just sufficient and just in time elaborated to focus on one item at the time implementing the functionality and marching towards sprint goal. (Let's pick more on sprint goal in later articles)
Sprint backlog is like your route map, it creates transparency for everyone to understand what is your plan to reach the goal. Of Course, the goal is fixed while the plan to reach the goal is flexible and negotiated. 
Freezing the sprint backlog makes the plan fixed and no scope for adaptability, this results in the myth everything listed in the sprint backlog is SPRINT GOAL ! and not finishing it, is a failure of the team.
Changes to the sprint backlog could be as simple as 
. Updates to the plan, adding missed items,
. Update estimates based on their inspect, adapt strategy
. Ownership changes on the activities
. Re-plan for effectiveness
. Elaborate the plan just sufficient
Remember Sprint Backlog is owned by the development team for them to self-organize toward sprint goal. Sprint backlog can be written in various formats. Tasks is one of the most widely used format, that's because of the costly licence fee paid to "Agile tools".. don't allow teams to plan in other formats.
Most of the teams I work with don't write tasks during sprint planning meeting. !!! yet they produce winning products.