In a scrum team, how important is it to complete a single story before moving on?
Our scrum master is fairly dogmatic about bringing a single story to completion before moving on. I can see that development would appear to be more “controlled” in this scenario, plus the scrum master would have a very accurate picture of what team members were working on at any given time… but I am interested in what this really buys us?
Clearly the scrum master wants to minimise divergence of the burndown from reality to avoid a shock come the end of the sprint – but surely if the sprint is two weeks long, the burndown is updated consistently and blockers are communicated at standups – any such divergence will be constrained by the sprint length, and be made visible mid-sprint through the usual channels (i.e. the standup or speaking to the scrum master individually). Any remaining issues can be dealt with in the fortnightly retrospective.
The reason for the question is that I seem to find I work most efficiently by keeping say 2 (or 3 if one is particularly easy) stories in progress at any given time which I work on as I see fit. This seems to assist with the sub-conscious background thought that assists with completion of the task. It also permits me to better understand the bigger picture if a couple of stories are related.
Our stories usually work out to be one or two days worth of work.
So, is working on a couple stories at a time frowned upon and if so what does one-story-at-a-time buy you?
i think it really is up to the team to decide. i think you hit it in your write up about the burndown, the most important thing is to meet your sprint commitments consistently. how that happens really should be up to the team if they truly are self-governing. the team im on now, our norm is to work on multiple stories at once; its the nature of our setup given that we try to really spread ownership of stories across the team. it may be a different norm for yours if you have shorter stories and more of a individual ownership style.