Nagib Choueiri asks:
How can time span differentiate between the time required to complete the job as a result of the job complexity or the individual's proficiency? For example, a more experienced programmer would finish a job faster than a less experienced one, so how can the manager determine the time span of the job irrespective of the individual performing it?
To answer your question, let's get down to fundamentals.
First, time span is about intended time (referred to by Jaques as "kairos") not about the time it has taken to complete something ("chronos"). Time span is the longest the manager intends a subordinate to take to complete any task within their role.
Of course, the manager's intention will typically be based on their experience of how long this type of task takes. And as Nagib correctly points out, the manager will expect a particular task to be done quicker by a more capable employee than it would by a less capable one. Here is where we must move our focus from the task to the role.
Let's consider Employee A in Role A and the more capable Employee B in Role B. And let's use the formula for task assignment: QQT/R (Quantity, Quality, Time, Resources). For the same QQ/R, the manager will give a bigger T to A than they would to B. B is more capable and so can complete quantity of output at the same quality standard with the same resources in less time than B can. But our 50+ years of experience using time span teaches us to predict that role B will contain within it a task longer than (with a bigger T) any task in Role A. The manager will understand that B can handle more complex work than A can, and some of that work will take longer than any task A can handle.
It is conceivable that a role could contain only compressed tasks, that is, tasks that:
- normally are given to someone at a given level of capability and which take a given amount of time but which
- have been given to someone at a higher level of capability who is given less time for them.
I asked Dr. Jaques about this some years ago and he said those roles are rare because they burn out the incumbent; we have a need, he believed, to extend our work out into the future as far as we are capable. It has taught me to be sure when I am time spanning a role that it is not a burnout role.
Let's look at the second part of your question, "How can the manager determine the time span of the job irrespective of the individual performing it?" On the one hand, literally, the manager must simply find the longest they intend the subordinate to take to complete any task within their role. But many roles do get adapted to the incumbent. The manager may have hired Employee B expecting them to perform as Employee A did. In finding B's higher capability, the manager will likely make two changes in task assignment to B:
- they will give B less time to complete a given task than they would to A
- they will give B more complex tasks than they would give to A, and some of those tasks will be given a longer T than in any task in Role A
Try this out while you time span roles, Nagib, and let me know what you find.