I love using this activity to demonstrate the harmful effects of overadjusting a process. It is a variation of Deming’s Funnel Experiment – and a big shout out to Steve Holcomb who first introduced me to this concept!
You will need four groups of 3 to 5 people each and a time allotment of 30 minutes.
Materials needed are:
- One pack of playing cards per team
- Four tape measurers
- Four colored dots to serve as the “target” – one colored dot for each team
- A dozen colored dots of a different color to serve as the last targeted position for Team B
- “Rule cards” for each team
- A data collection form for each team (optional)
You will want to use a room large enough for four teams of people to stand and work in small circles. Place a colored dot in the center of each of the four teams. Prior to the session, place one colored dot or “target” on the floor for each of the four teams. Each team will be congregating around the dot – so you need to make sure there is enough room for all to do this exercise comfortably.
Divide the team members into four teams. Tell each group to go stand around their designated dot on the floor, or “targets.”
Tell the teams that the objective of this exercise is to produce as many products as close to the target as possible while following their particular “rule.” Hold up the four cards for all to see.
Tell the teams that they produce product by dropping one playing card from shoulder height. Demonstrate dropping the card – drop the card perpendicular (not horizontal) to the colored dot or “target” on the floor; this provides the most variation!
Reiterate the goal: to produce as many products as close to the target as possible, while following their particular rule. Hand out one deck of playing cards, tape measure and one “rule card” to each team. Go over the rules for each team:
- Team A: Don’t adjust. Drop every card over the target.
- Team B: After each drop, measure the distance (z) from the target to the spot where the card landed. Set the next drop position over the point (-z) from the last targeted position. Use the additional colored dots to mark your last targeted position.
- Team C: After each drop, measure the distance (z) from the target to the spot where the card landed. Set the next drop position over the point (-z) from the target (same distance, but opposite direction).
- Team D: Set the next drop position right over the spot where the last dropped card landed.
Allow the teams to produce a dozen or so products. Pay particular attention to teams B and C; their rules are the toughest to follow.
Debrief and Summarize
After all have finished dropping at least twelve cards, review the distribution of cards with the entire group:
- Ask the team to share the rule it followed.
- Ask the team to share the results and speculate what happened to its process.
- Ask the team to share an example of where it sees the same type of pattern happening.
Team A: The cards will tend to be clustered around the target. The distribution is stable with minimum variation around the target. Even if you have a bad process, you’ll get an
even distribution. This is a stable process, and by far, the best choice.
Team B: The variation explodes and is unstable but symmetrical around the target, as we tamper with the process. The operator knows where the standard is, but adjusts based on the last piece produced – and where he or she thinks it should be. Like setting an oven to bake a cake, if we know from past experience that the oven was too hot, we’ll adjust the control to be a smidgen less than it was when we baked our cake before.
Team C: The distribution explodes in opposite directions, as we overcompensated for our errors. This is the way most processes are overadjusted from where the operation was during the last process run. Like a novice driver steering a car, the operator overadjusts (or management overreacts!).
Team D: The cards will tend to drift. The distribution is unstable and moves away from the target in one direction. This is the kind of process drift that can occur when we use the last piece produced as the standard for the next piece, instead of a universal product standard. Drifting also occurs when we let experienced employees “show the ropes” to new employees, without any training standard.
Have each team come up with its own examples of losses in its organization resulting from Rules B, C, and D. If possible, ask the team members to estimate the losses to the organization.
Close with a discussion of how organizations take a stable process and try to make it better. The result of our efforts will only make it worse – double the variance or cause the process to explode. What is required is a fundamental change in the system.
Super important! You will want to do a dry run of this activity. Of all the Team Activities in my book, Team Energizers, this is the most complex, so make sure you understand the four rules and see how it plays out before you do this with your team.
If time permits, do another “round,” allowing the teams to make process improvements. Have each team identify one improvement to make, test it, and then compare the results. For example, one process improvement might be to hold the card parallel to the floor before dropping it. The result using Rule A will be that almost every card will settle down on top of the target!
If you like this activity, check out my book, Team Energizers, for 49 other team activities.
Inspired by W. Edwards Deming and Steve Holcomb
2001 American Society for Quality
Deming, W.E. (1986). Out of the Crisis. Cambridge, MA: MIT Press.