Time Tracking in Scrum
Note : Before asking this question I did an exhaustive search, and found little bits of the answer in various other questions, for example:
- What is the best resource for learning Scrum?
- Scrum Process Management - tips, pitfalls, ideas
- Two questions regarding Scrum
However, I feel like this question hasn't been directly addressed (if it has, please let me know).
Do you track time in Scrum as a function of hours/days spent on a task, or simply whether that task is complete or not? Can you adjust those tasks and estimates?
Background: Our new VP of development came from a Scrum environment, and so we're all learning about the process, but one of the things he has brought with him is the concept of very carefully quoting estimates of actual hours each task should require to complete, with the intention of getting more accurate with our estimates over time: thus once a project has started we cannot add new tasks or adjust the hourly estimates on those tasks.
But it was my understanding that agile practices, specifically Scrum, were based upon the concept of tasks being buckets that store individual deliverable goals, and you add/remove/adjust them as the clients' needs evolve after each sprint.
I realize this could potentially be argumentative, but I assume that viewing Scrum as a process, only one of those concepts is the "correct" philosophy for that system.
Answer
Do you track time in Scrum as a function of hours/days spent on a task, or simply whether that task is complete or not?
I track the estimated remaining work. This is a must have information. Without this, you can't draw the Burndown Chart. Without the Burndown Chart, you don't know "where" you are, you don't know if your Sprint is still on track or not. This would make this decision tool pretty useless. Yes, the Burndown Chart is not a tracking tool, it's a decision tool.
Can you adjust those tasks and estimates?
Sure!
Actually, the team owns the estimates, nobody else, and it is the job of the ScrumMaster to guaranty that this principle is applied. This should already answer the question. But there are other reasons.
As I said, a Sprint Backlog and a Burndown chart are decision tools and should thus be representative of where you really are. If you hide the reality, if you are not transparent, these tools won't help you to take any valuable decision, they will be useless. Think about it, what's the point of having good looking numbers if they are useless? What's the point of having a "nice looking burndown" if it doesn't reflect the reality.
So, during a Sprint, team members should obviously update the estimations of the remaining work as soon as they can do it (upward or downward). If a task estimate was initially 6h but the team discovers that more work has to be done and that the task will actually take 8h, the team should update the Sprint Backlog accordingly. If someone spent 4h hours on a task that was initially estimated at 4h but still need 2h work, these 2h should be reported on the Sprint Backlog. If the team discovers a task that has to be done but that wasn't identified, the team must add this task and its estimate to the Sprint Backlog. And being not accurate in the start is not a problem, as long as you update the backlog with the knowledge gathered over time. The sooner you make these updates, the sooner you'll be able to adapt and take decisions.
That said, it can be useful to keep the "initial estimate" and to compare it to the "actual time spent to complete". But not for tracking purpose, only to help the team to make better estimates. Actually, I would advice to not do this if you are transitioning to Scrum. There are often many other impediments to solve, many other things to improve first when you are learning Scrum values and principles. And if you do it, beware of the Waterfall daemons. Be ready to fight them, they may come back very fast.