Flow Efficiency, a Health-System parable

Meet Alice. She is ill, and she depends on the public health system to discover and treat her disease.

She books an appointment with her GP in one week when there is availability (the GP is busy seeing other patients until then).

In the appointment, Alice is asked to find a specialist for further analysis. The specialist is only available in two weeks (he is also busy seeing other patients).

The appointment with the specialist happens, and Alice is requested to do some particular exams to help diagnose the problem. The equipment necessary is scarce, and it's only available in another two weeks' time (given the scarcity, the equipment is busy, operating close to a 100% utilisation). Alice was asked to come back to the specialist with the results.

Finally, the day comes; Alice does the exams and calls to book the return to the specialist, who is available just in another week.

Unfortunately, the exams weren't enough to diagnose, and another particular exam was requested, making Alice go again in the saga.

The next round, luckily, the exam was conclusive; they found what was causing the problem, and now Alice needs surgery, which in the public health system, she will only be able to do in three weeks and eventually get cured.

In that parable, doctors and machines were very efficient and operating close to 100% utilisation. Day in and day out, they were Next! Next! Next! They were working relentlessly, hoping not to break (themselves or any machine), as they knew the queue just kept growing.

Now, looking from the patient's perspective. It took her 12 weeks to diagnose and treat her disease. That is 84 days or 2016 hours.

She had during this time four doctor appointments (25min each), three exams (20 min each) and one surgery (3 hours), summing 5 hours.

Five hours of value-added time within 2016 hours of treatment, which means 0.25%.

Resources efficiency: close to 100%

Flow efficiency: close to 0%

Alice is your feature in the backlog. Doctors and specialists are your delivery function with all the silos. The special exams are your constrained resources or shared functions in your delivery function, such as DBA, Security, UX, etc.

In corporate, when dealing with knowledge work, people are working close to 100% utilisation to the detriment of the efficiency in which the work flows throughout the value stream. This number usually turns around 5–15%.

In other words, on average, all of your pieces of work are idling in queues for about 85% of their time and just being touched on 15% of the time.

That's your invisible killer!

I hope this content has pollinated your ideas.

Till the next time!

Marcio Sete