Engineers and designers explain that, being people themselves, they understand people, but this argument is flawed. Engineers and designers simultaneously know too much and too little. They know too much about the technology and too little about how other people live their lives and do their activities. In addition, anyone involved with a product is so close to the technical details, to the design difficulties, and to the project issues that they are unable to view the product the way an unattached person can.
I found this passage very interesting because it explains that it is very difficult for engineers and designers to experience the same problems as the consumer. This is because the engineers and designers know a wide range of problems that can occur accompanied by a wide range of solutions. However, the consumer may not know what to do when a certain problem arises. Also, the engineers and designers include many unnecessary features that they think may be useful to the consumer but in reality they only complicate the product. As Norman said, the engineers and designers know too much about the product itself and not enough about the people who use the product.
The categories defined by Norman - visceral design, behavioral design, and reflective design - seem very useful to me. During the design process, it helps a substantial amount to know what type of product you want to make and how you want to design it. These categories help the engineers and designers make these decisions. I believe that these categories are well named and in a way they all define themselves in the name.
A designer can decide which level of design he would like to use by choosing what type of impact he would like to make on the market. If the designer is looking to make a quality product that satisfies the needs of the people who use the product, he would use behavioral design. If the designer wants to make a product that can be sold for a high price and used as a display of prestige, he would use reflective design. Finally, if the designer wanted to make a product that attracts the general public by the look and/or feel of the product, he would use visceral design. Many types of products are more of one design than the other. This all depends on what the main focus of the product is, and what the designer is going for.