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design:half_the_battle

Half the Battle

Half the battle of developing a new product is just understanding the design problem. Without understanding the problem deeply and broadly, it is more likely that the decisions made during design will be wrong.

Why is this so bad?

Fig. 1: The curves approximate the rate of increase of cost required to correct for two design errors, one early in the process and the other later in the process. It is much more expensive to recover from errors that occur early in the design process. So the most important design decisions are the early ones.

Consider figure 1. Time is on the horizontal axis; cost is on the vertical axis. The curves approximate the total cost (human resources, equipment, time, rework, scrap, overhead costs, etc) needed to correct two design errors. One error occurs at the very beginning of the design process. The other error occurs about mid-way through the design process. However, both errors are only noticed at some later time, marked by the Ooops! line.

Exercise for the reader Consider the relative cost of the two errors. Which one is more expensive? Why? Make lists of the kinds of errors that are represented by each of the two curves in Figure 1. What do the errors in each of your lists have in common? What does this mean for designers and what they should know?

The phenomenon shown in figure 1 is known as the Pareto Principle (aka the 80/20 rule). In design settings, it is usually phrased as: 80% of a product is determined by the decisions made in the first 20% of the product development process.

So, design errors that occur at the beginning of a design process are the most critical errors.

What causes a design error? A bad decision.

So to avoid early errors in a design project, the decisions made during the early design stages are the most important.

To make good decisions, you need three things:

  1. good information about the decision alternatives
  2. good decision-making methods
  3. expertise

For the moment we are interested in the first item: information. Good information about the design is needed to make the best possible decisions in a design process. The most important decisions are the ones at the beginning of a design process.

So the most important information is information about the initial design problem that has to be solved by developing a product. That's why understanding the problem is half the battle.

The first step in any design project, then, is understanding what the real problem is that needs to be solved1).

When working in teams, it is especially important that the whole team understand the same problem. An engine gasket case study highlights what can go wrong when this is not the case.

If some people on the team are working with false assumptions or bad information, then they will work toward a slightly different goal than the rest of the team. If some people on the team are working on slightly different problems, even if their information is correct, then the result will be a bad design.

Much of the “paperwork” in real-world design environments is really meant to make sure that everyone – designers, engineers, technicians, and management – all agree on exactly what they are trying to do.

design/half_the_battle.txt · Last modified: 2021.07.04 17:57 by Fil Salustri