Steven Arbogast has written a seminal article about Process Towers and how they can spoil the Process Improvement you can effect in any part of an end-to-end business process.
Steven uses an excellent example of a waiter taking your order at a restaurant with many variations, and special requests you may ask for, after looking at a menu. They usually have very little time to take down all these variations on a little slip of paper that they pass on to the kitchen. Between your order and the eating, many things can go wrong in the handoffs between the waiter, the kitchen, and the one or more chefs that may prepare what you ask for!
End-to-end processes may have many process towers in between, that can make a process go horribly wrong. In the end, it does not matter to the end customer, who among the process towers got things wrong about your order! Handoffs between processes are very sensitive and may need as much watching, as the process itself!
Process measurement is where these process towers can make sure that these handoffs are handled properly. Upstream Metrics and Downstream Metrics may need as much watching as the Process Metrics themselves. Each process may need to make sure that the handoffs from the previous process tower is done according to expectations – For an order management process to work properly, the previous order taking process tower may need to make sure that they handoff things properly. This is done by the Upstream Metrics. Once the order management process tower is done, handoffs to the production process tower may need to be handled properly. These can be ensured by the Downstream Metrics.
Process Towers are scary. Handoffs between them could wipe out any gains you may effect in any one single process tower. However, with proper management of metrics, Upstream and Downstream, from a proper process tower can ensure that handoffs are managed properly.
There’s many a slip twixt cup and lip – Proverb
