Disciplined Agile

The Knowledge Work Highway

When you are operating at capacity or beyond, you cannot say “yes” to a request until you say “no” to something else!

This is true whatever your domain: tangible, intangible, or social products or services. This article looks at intangible knowledge work but the concepts apply across the board.


Throughput or Wait Time?

One challenge for knowledge work is that the capacity of the organization to deliver solutions is rather abstract. It can be difficult to quantify. You cannot observe and count the widgets of knowledge work being produced. The inputs – requests for desired functionality – are abstract. The value of adding yet another feature request to a list of requirements or of adding yet another project to a portfolio of projects can be guessed but cannot be counted. And yet, we know that the “volume” of inputs can clog the system.

Imagine traffic on a one mile stretch of highway. What is the throughput capacity of the highway? You could put a counter at the end of the stretch to count the number of cars per minute.

The manager of the highway wants to maximize the throughput of the highway and so begins to add more and more cars onto the road. At first, the throughput goes up and up with each car added. If each car is moving at 60 mph, then the average wait time for each car on that one-mile stretch is one minute. The manager assumes they can keep adding cars and so maximize the capacity utilization of the road. That works for a while.

However at some point, way before we reach 100% of the number of cars that can fit on that one-mile stretch, the throughput stops increasing. Even worse, the average waiting time for cars starts to increase as the cars start to go slower due to random breaking or stress or variations. The cause is not always apparent, but we have all seen it when stuck in traffic jams.

By focusing on maximizing throughput, the manager has in fact increased waiting time. As we approach the capacity limit of any system, wait times inevitably increase. It would have been better to pay attention to delays, to the wait times, in order to get the most throughput.


The Knowledge Work Highway

What does this have to do with knowledge work and capacity?

Traditionally, we have tended to treat knowledge work capacity like an uncrowded highway, where we keep adding requirements without a thought about the impact on waiting time.

The lean value stream is our “knowledge work highway.” Its purpose is to bring visibility to the work required to get from initial idea to a solution consumed by the customer.

For example, consider two service delivery organizations. Both organizations seeks to deliver 60 features at the end of the year.

  • One organization bundles all 60 feature requests into annual projects due at the end of the year.
  • One organization groups the requests into batches of five per month.

Both have the same annual throughput of 60 features per year, but which is better?

For the first organization, the soonest any particular feature request can be delivered is one year, even if a feature is incredibly valuable. The second organization could deliver that valuable feature in one month. Both organizations have the same annual throughput, but the second organization realizes value sooner.

The second organization is focused on the cost of delay.


Focus on Delivering Value

Lean thinking places a premium on how long the customer has to wait in order to realize value. Improving the value stream is driven by reducing delays, wait time. Managing queues and not overloading knowledge work capacity are ways to help improve flow and reduce wait time.

Instead of focusing on throughput, the right question to ask is what is the highest business value that can be delivered in the least amount of time. This simple change in perspective is to see the true measure of productivity, which is the time required to get any one request through the system.

Here are some lessons for your organization.

  • Measure the time it takes for high value consumable features to be created and released. Make this wait time visible to everyone. Focus improvement efforts on driving down this wait time.
  • Create and make visible to the entire organization the sequenced priority of work. Focus on completing that work according to that sequence.
  • Minimize the number of work items open (at all levels). This will minimize wait time and maximize value delivered.