Concept of Batch Size in Scrum with Kanban
Ideally when we reduce batch size, efficiency increases. As the amount of actual work during Work in Progress is reduced or we can say through any stages in the KanBan Board. Can there be a case that reducing our batch size backfires (yes DT is not challenging itself & not progressive). Or in other words If we reduce our batch size, overall efficiency will ALWAYS increase? Appreciate your views.
Anything above a batch size of 1 implies flow debt. The time which could be spent completing an item is spent elsewhere, and so it remains in progress. Note that this applies to Product Backlog items rather than technical tasks, which effectively just constitute a plan for value completion.
Like any other form of debt, including technical debt, it can be worthwhile incurring flow debt in certain circumstances. A high-value item might be expedited instead, for example. However the justification for doing so is much rarer and weaker than you might suppose.
Imagine carrying shopping bags home from the supermarket.
What would the ideal batch size of shopping bags be? For many it would be 2 to 4.
Most people are able to carry at least one bag in each hand, so in such a case, the acceptance of a greater batch size (which perhaps has a very small effect on delivery time) could reduce other waste, such as the number of trips required to do shopping.
What does the data say when you experiment with different batch sizes?