I have noticed that team velocity sometimes becomes "negative" near to the end of a sprint. There's few trivial story's/bugs left but they took extraordinary effort to finish. Team seem's not to be exhausted. But this is always endangers and shifts delivery date. What i have tried:
- Micro-control - gives a little boost, but stress people, and against agile practices
- DYI - works but only if you know how
- Reduce the sprint backlog capacity to have a cooldown period where team could set all the things right. - Not working
- Introduced a redline, something like internal dead line where all of storys should be closed with all non trivial bugs. - Not working
- Shifted release to middle of a next sprint, and applied firefighting team who FINISH OFF tasks left. - Works but nobody want's to finish others job.
None of the listed methods are 100% working or satisfactory from stakeholders/management point of view.
Any ideas on nature of of things or suggestions on how to get rid of the issue?