iSixSigma

Hitting Target

Targets appear in all shapes & sizes. Sometimes seen as positive, “we operate a target-driven culture” and sometimes negative, “targets drive the wrong behaviour”. So what is true? Given the sheer diversity of targets, I want to focus on a specific area, daily work targets in a services environment. Let’s look at a scenario.

Imagine an operator works in a services business. Work comes in three types and timing tests show each type can be completed within 20 minutes inmost cases. Now imagine the operator being given items of work and being asked to work under two different management controls:

  • Control 1, Work items are targetted to be completed within 22 minutes.
  • Control 2, There are no targets and work items must be completed regardless of the time required

Statistically speaking, an assessment of the two approaches could be made, something like:

Ho = There is no difference between the time taken to completework items under control 1 or control 2

I am looking at running some tests to see if there is a difference as this is related to a project I am working. But what is your gut feel on the expected performance difference?

I have tried this in a very small trial and found that when working under a time target, you focus on the time target. As the pressure builds on any individual work item because you are watching the clock you find it more difficult to focus on the task in hand and end up missing the target. You lose valuable time because of the target.

So what does this show? Does this describe an example of why targets drive the wrong behaviour? Does it show that getting it right first time saves money? Does this show operator’s pulling work? Does this show a difference between batch and continuous flow?

I’m not sure but I feel I am looking at something quite important here, just not sure exactly what it is yet……..

Comments 3

  1. JConsidine

    Bill Bellows talks about 1-line vs 2-line thinking – spec limits vs. a target. There is a big difference between them, and not all situations need a target vs. an acceptable range. I believe the Taguchi loss function exposes the cost of variance from the target

    I often hear the phrase "Variance to Want" in our business – the customer wants their delivery when they want it – certainly not late, but not early either.

    Arbitrary targets, metrics, goals, etc, often cause more harm than good. But target thinking seems to me to be very in line with Lean, especially working to takt.

  2. Rob

    I’ve written about targets before on my blog. Deming said, "Management by numerical goal is an attempt to manage without knowledge of what to do”. Targets can be arbitrarily set and results improved by:

    1. distorting the system
    2. distorting the data
    3. improving the system (which tends to be more difficult though likely what is desired)

    Targets are a part of a system. They interact with the rest of the system. A numerical target focuses on the number not improving the process. Beware!

  3. Robin Barnwell

    Hi Rob/James
    Thanks for the feedback

    Rob, I read your comments; James I read your Blog, "What you measure is what you get?" and took a look Deming’s Out of Crisis. How could I have missed reading this one! I think it should be given to all new GB & BB as a must-read before starting work.

    James, you’ve run through a long list of tools and approaches here. Will take a look at Bill Bellows work. I think using Taguchi to sell the need for change with some of my stakeholders will be difficult. I looked at "standard work" and meeting takt time. I thought it might be another example of the issue and didn’t go down that avenue.

    I think I can state what I am trying to do. I am looking to very simply demonstrate the behaviour change that occurs when people have a specific target placed on them. I wish to demonstrate that people focus on the target rather than the quality of the their work.

    I was also recommended to look at Demming’s Red Bead Experiment. Any tips here would be useful.

    Robin

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