Why work grinds to a halt when you get busy

When things get busy work always seem to start to piling up. Typically this not a problem in itself; you start delegating some responsibilities and say "no" a few more times. At some point you just have to do the work – or decide not to. Things get iffy when you are too busy, too often. Naturally deadlines start to shift, but not only for the projects that you’re involved in knee-deep. Every single thing you touch starts to move at snail’s pace. How did it ever get to this?

The scenario above sounds probably too familiar for many senior employees. Their experience and inputs is valued across the organization, but their limited availability can become a major factor when considering lead times. Again, the solution is simple: cut down on responsibilities and availability improves. Having observed this problem a few times (and having falling victim to a few more times over) I got curious about the mechanics and did a little digging in operations management theory. Turns out I actually came across the answer years ago when reading The Phoenix Project.

Turns out this is a pretty well understood phenomenon and has its origins in queuing theory, namely Kingman's formula. The theory is a bit more nuanced, but it basically states the busier the resource (high utilization), the longer the lead time becomes (wait time). Makes sense, right? If you have nothing on your plate you can instantly help out a colleague. When you’re swamped it’s much harder to find a way to fit their request into your schedule. Especially when it takes a lot of time to complete.

Imagine a project requiring the attention of multiple highly utilized resources throughout a project. It is not hard to understand why the lead time of the overall project comes to a stand still (also have a look at Little’s Law).

But what are the actual implications for project managers? Further division of labor, which allow tasks to be performed by more team members is one solution, but this becomes less feasible for work that is hard to standardize. It will also likely increase the number of handoffs required to complete a project. Not a great solution.

Looking at other components of Kingman’s formula tells us that larger-than-normal tasks also influence wait times. In practice this means that well-defined requests are more likely to be returned within acceptable wait time. Don’t waste your senior employee’s time if somebody else could have done a better job at defining the actual problem and structuring the information required to complete the request. This actually holds for many other situations; the easier a question is to answer, the more likely you are to receive an answer. 

It is hard to stress the importance of senior employees in an organization. They are true "value multipliers" in the sense that their insights often drive a project forward. They are critical to maintain quality, reinforce culture and train other employees. This explains why it’s great to have them involved and possibly counterproductive to devise methods to remove them from projects. So how do we solve this paradox?

Another hard look at the graph shows that wait times only become problematic when utilizations rates cross the 90%. Simply maintaining a healthy ratio of junior/senior team members and ensuring your seniors have some additional slack should yield adequate lead times. This means team members get their work done faster, project throughput increases and clients get their projects delivered earlier. Isn’t it great when you solve a problem that benefits all stakeholders?