Thirty Agile Austiners attended a free lunch at Kasasa to discuss with value of time boxing a sprint.
What are benefits of timebox?
Predictability / Focus Priorities / Cadence / Estimation / well documented, it comes in a box
Problems with Timebox:
1. If testing takes four days at the end of a sprint, what are the developers doing those last four days?
Timebox encourages crossfunctional team members; developers that test the last few days. Is this the best use of their time?
2. No room to do important bug fixes or building infrastructure. Too much noise to estimate accurately.
3. Have to do lots of padding for noise.
4. Poor quality, and no refactoring, results from cramming something in at the last minute.
5. Timebox has a negative effect on morale, as a sprint is considered a failure if only 9 of 10 items were done. When this goes on sprint after sprint morale suffers. Then developers start to pad estimates which then starts to look excessive.
Kanban - one piece flow - watch a single work item carefully to see blockers
Kanban is flow based, Scrum is iteration based.