JUST AS THERE ARE many potential causes and root causes for any problem, there is always more than one way to solve any problem! The creativity of the problem solver is an important aspect of the Toyota Way of thinking, so there are few absolutes regarding the best approach; however, there are some key concepts to guide the evaluation process. The typical process would include:
1. Broadly consider all possibilities.
2. Narrow the list by eliminating impractical solutions or combining similar items.
3. Evaluate based on simplicity, cost, area of control, and the ability to implement quickly.
4. Develop consensus on the proposed solution.
5. Test ideas for effectiveness.
6. Select the best solution.
Broadly Consider All Possibilities
Many a young engineer at Toyota has worked very hard to detail a solution with great pride. He or she shows the solution to his boss or mentor with great enthusiasm and a bit of trepidation, since the mentor is an expert in the field and will find some weakness in the proposal. The mentor barely bothers to go through the solution and supporting documentation but instead asks if that is the only solution considered. The young engineer explains that the documentation supports the conclusion that this is a good solution. “But could there not be even better solutions?” the mentor asks. So it’s back to the drawing board to identify other potential solutions. The mentor may in fact think it is a perfectly good solution. What he or she is trying to teach is a way of thinking.
The Toyota Way documented the case of the Prius development. With intense pressure to get out this first production hybrid vehicle on an unreasonably short timeline, the chief engineer still decided to explore many possible solutions. Chief Engineer Uchiyamada asked the engine group to identify all viable hybrid engines, a total of 80, which were winnowed down to 10, and then four that were simulated on a computer before one was finally selected. Similarly, when selecting the styling for the vehicle, he held a competition among four Toyota design studios in Toyota City, Tokyo, Paris, and Calty, California, generating 20 alternative designs and then five detailed sketches, four full-size clay models, and then two exceptional designs. Those two designs were thoroughly evaluated, and the contributing studios in California and Japan were asked to make an additional round of improvements before the California design finally won.
There are many ways to generate a list of alternatives, including the use of competing groups in developing the Prius. And one useful technique for a group of people involved in a project is “brainstorming.” Many companies tried it when they experimented with the “team concept,” but it was viewed as only part of team activities and eventually fell out of favor. In fact, brainstorming is useful in ensuring the thorough evaluation of a subject. The failing of brainstorming is often that the problem was not well analyzed to begin with, and the process of evaluating solutions and narrowing down to a preferred solution is not well understood.
Simplicity, Cost, Area of Control, and the Ability to Implement Quickly
An evaluation whose criteria are simplicity, cost, area of control, and the ability to implement quickly will ensure implementation of the most cost effective solutions. But first, ideas that won’t effectively work as countermeasures should be removed from consideration.
During the brainstorming process, many wacky or impractical ideas may be presented. This is true by design since a rule of brainstorming is that “there is no bad idea” and ideas suggested should not be evaluated until the brainstorming is complete. While a quantity of thought-provoking ideas is desirable during the brainstorming session, not every idea deserves consideration as a viable solution. Those ideas that don’t should be removed from the list by either eliminating them outright or combining similar concepts into a common one. A short list of ideas can then be evaluated.
Our four criteria can now be put to use in evaluating this short list of solutions that can possibly solve the problem:
- Is it within your control to implement? (Can you do it without outside support?)
- Is it possible to implement the solution quickly? (Today is best.)
- Is the solution a simple one?
- Is the solution low cost, or even better, no cost?
- Will the solution be effective as a countermeasure?
Each of these evaluation criteria is interdependent, and it’s usually not possible to meet one without meeting the others. For example, a solution may be identified that involves purchasing a new machine (“If we had that machine, we could make more parts”). This solution would violate four of the criteria. It’s unlikely that the purchase of new equipment is entirely within your control. Even if it were, the solution could not be implemented quickly and it’s certainly not low cost or simple to do.
If the evaluation criteria are utilized, a pattern of certain types of solutions will begin to emerge. The types of solutions often considered first at Toyota are methodology changes. It is easy to change the method of work. Simply ask the worker to change the way the work is done. The control of work methods is generally within the direct supervisor’s realm. The cost of changing work methods is minimal—–it may require a new table, tool, fixture, etc.—and it can be changed immediately!
Using the above four evaluation criteria will considerably narrow the list of possible solutions. It will make it easier to develop consensus on the best possible solution because of fewer choices, and personal bias and subjectivity that might influence the choice of the best solutions are removed. Now, if the choice is narrowed to two or three possibilities and it’s not possible to reach consensus on one of them, proceed to the next step: Test each idea to prove its effectiveness so the merits and demerits of each will be apparent. In most cases, testing will reduce the possible solutions to the best one, making it easier to reach consensus.
It should be noted that “consensus” does not imply complete agreement with the proposed solution. We often hear managers discussing the difficulty of getting employees to “buy in” to the changes. This is a misguided belief that it’s necessary for everyone to agree and want the change. In fact, consensus means that everyone agrees to accept the proposed solution, even if they don’t believe it’s the best one. Any disagreements regarding “my way” versus “your way” are easily resolved by agreeing to try both methods and then let everyone see “the best.” There are a few exceptions where a clear winner is not obvious, in which case a vote or similar method can be used to determine the preferred choice.
The model of continuous improvement suggests that all things will continue to evolve, so any idea implemented today may be changed tomorrow. Generally,if the process has been followed carefully and everyone clearly understands the root cause, reaching agreement on a proposed solution is relatively simple. Consensus is gained at each step of the process, and by this stage most people are “on board” with the solutions and ready to implement them!
Test Ideas for Effectiveness
It’s important to verify the effectiveness of the planned solution before implementing it. This is done prior to developing an implementation plan. There is little to gain from pursuing a solution that has little likelihood of success. Toyota’s ability to create significant results is largely dependent on the certainty of those results, prior to beginning any implementation.
How does Toyota prove an idea without actually implementing it? Following the scientific method, an experiment is designed, allowing the effect of implementation to be simulated. This simulation is “real world,” occurring in the workplace whenever possible. When it’s not practical to test in the real world (such as machinery movement), a cardboard or even wood mock-up of the work area is used to verify the idea.
For example, take the following root cause: “Excess walking due to poor layout.” For a simulation technique, the implementer can “assume the waste,” with a team member presenting material to the operator “as if” it were already relocated. In this way the operator can perform the work with the waste temporarily removed. The team member can also experiment with the most effective material placement by holding the material in different positions. This allows the operator and the team member to see firsthand the most effective presentation, and it aids in the design of material presentation devices such as carts, flow racks, chutes, etc. The operator can provide direct feedback, and the team member can experience the pluses and the minuses of any method.
The operator work flow during the simulation is diagrammed in Figure 16-1.
The dashed lines represent the steps of the team member who will return to the parts supply to retrieve the next part and present it to the operator at Step 1, demonstrating the effect of improved material placement. This will shorten the operator’s walking time, and the resulting reduction in cycle time can easily be measured with a stopwatch.
Further tests can be conducted to demonstrate the effects of relocating the inspection process and the finished parts container. Completion of the improved work flow is shown in Figure 16-2.
It is important during a simulation to respect the needs of the person doing the work. The simulation must be accomplished without disrupting the work process or stopping the operation. It is the implementer’s responsibility to be aware of the situation and stop any testing if it’s having a negative impact on the operator. Of course, safety is always the first consideration, and the implementer must observe any changes for possible safety issues, including negative ergonomic impact.
Figure 16-1. Simulated work pattern with walking removed
Figure 16-2. Completed work layout
After the basic idea has been tested and necessary adjustments made, full implementation is possible. If the solution was tested effectively, the need for further adjustments will be minimized.
Select the Best Solution
Based on the simulation, the best option among the solutions is selected and the implementation scheduled. Occasionally, an idea is tested, and it is then discovered that the idea is impractical or difficult to sustain. Discovering this during the testing stage provides the implementer with firsthand understanding of the shortcoming in thinking. (Note that Toyota would not say that an idea is “bad,” but that the thinking was not complete.) The operator also sees that the implementer recognizes the shortcoming and therefore does not need to worry that an ineffective solution will be proposed (and that they will be stuck with the faulty solution). Returning to the list of possible solutions will generally provide an alternative possibility, which also must be tested and proven.
Define the Right Problem and the Solution Will Follow
You may notice that this chapter is relatively short in comparison to the previous two chapters. This parallels the reality that the bulk of the problemsolving effort is in defining a problem and analyzing it to find the root causes. If the root causes are found, the answer is often obvious and easy to understand. The greatest challenges in this stage of evaluation are keeping the solutions related to the problem at hand, focusing on the issues that are within the control and responsibility of the individual or team, and identifying simple solutions that can be done quickly (today is always best!). The leader must continually redirect the effort and ensure that is stays on track. He or she must challenge people to think creatively and explore alternatives with questions such as “Why did you select this solution?” and “What other alternatives did you explore?”
Toyota managers have mastered the problem-solving methodology and have an exceptional success rate. Careful analysis based on facts allows them to determine the benefits prior to actual implementation, and testing and verification of possible solutions allows them to completely understand the effectiveness before choosing the best options. They continually aim, aim, aim, to make certain that the target will be hit—a dead bull’s-eye!
1. Present at least two potential solutions for each root cause you identified in the previous chapter. Review your proposals with others, and double the possible solutions (to at least four) for each root cause. This may challenge your thinking, but don’t give up until the list is doubled.
2. Using a matrix to evaluate each solution, rank them based on the following criteria:
a. Is the proposed solution within your control to implement?
b. Is it simple (preferably a method change)?
c. Is it possible to implement the proposed solution quickly?
d. Which of the proposed solutions can be implemented for the least cost?
3. Without actual implementation, develop a method to test each viable solution that met the above criteria.
a. Do any of the proposals need to be modified to more effectively correct the root cause?
b. What method will be used to verify the effectiveness of each proposal?
c. Quantify the potential benefit versus the cost for each solution.