“How far are you with this task?”. This question is quickly asked and chances that you get an answer like “we are 80% done” are very high.
Does such an answer really makes sense? How do humans assess the progress of a task? According to the Pareto principle we might need 80% of the effort to fulfill the last 20% of the task, but most likely we perceive this differently (more linear). So even if we have the best intentions, the human brain is being tricked here.
So what are the options?
There are a couple of ways to report the completion of a task (see e.g. Rob Thomsett: Radical Project Management):
- binary (0-100): Either a task is finished or considered as not yet started
- binary (50-100): As soon as a task has been started, it is considered as 50% done
- linear: If a task is scheduled to take 10 days and 8 have been spend on that task it is 80% done. This is the Microsoft Project way
- subjective: Most often used in ad hoc reporting. The team is asked and tells their gut feeling (more or less)
The advantage of the binary strategies is that you are not tricked by the nonlinearity of things. There is no false security of having plenty of time.
And there is another positive effect: Designing tasks to be suitable for binary evaluation. By the team being aware that a task is either done or not, they will most likely start to design tasks that are actually suited for this approach: Not too big but still one entity. However it is very critical to resist the tendency of making tasks too small (to get them done quickly). Unfortunately there is no rule of thumb of how long a “standard” task should be (do not trust anybody who states otherwise).
There is another very important aspect to this: Defining the task in general and the criteria of completion in particular is key. As said above, a task needs to be a kind of atomic effort. You should not confuse this with an artifact or deliverable. A task can be a part of an unfinished deliverable but needs to have clear completion criteria.
Binary reporting also prevents micro management. The team will report the task done, when it is done. Asking beforehand does not make much sense as the binary answer is not done yet (either 0% or 50%). Having said this, it is the responsibility of the person or team that owns the task to escalate in time when they see a risk of not being able to complete the task in time.
Whatever you do, always remember to keep a buffer in project planning… But this might be another post.
Update 2007-03-01: Johanna Rothman has a post on this topic: There is not such a thing as Percent complete.