too much anxiety produces a phenomenon known as “tunnel vision,” where the people become so focused they may fail to see otherwise obvious alternatives.

Another important dimension for a product is its appropriateness to setting.

At the visceral level, physical features—look, feel, and sound—dominate.

enhancement and innovation. Enhancement means to take some existing product or service and make it better. Innovation provides a completely new way of doing something, or a completely new thing to do, something that was not possible before.

Perhaps the objects that are the most intimate and direct are those that we construct ourselves,

If you design according to these rules, your design will always be attractive,

If you design for the sophisticated, for the reflective level, your design can readily become dated because this level is sensitive to cultural differences, trends in fashion, and continual fluctuation.

the “wow” factor.

The trained observer can often spot difficulties and solutions that even the person experiencing them does not consciously recognize.