Lidwell, Holden, and Butler state in their article Consistency that when there is consistency in the design and function of a system, that system is easier to use and learn. There are four kinds of consistency: aesthetic consistency dealing with style and appearance, functional consistency which refers to meaning and action, internal consistency with other elements of the system and external consistency with other elements of the greater environment. The article states that these things communicate expectations of trust and recognition with audiences.
This phenomenon is believed to be a continuation of human beings learning from “integrative unity” from early infancy. That is the way one grows to relate to existing variety in the world. Because of a person’s faith in unity, trust is built up through certain things. Fire burns, a parent brings love, falling down hurts etc. This consistency in life translates perfectly to systems.
Designers have most definitely picked up on this. In this saturated world of products and brands aesthetic and external consistency can bring much needed attention and increases the probability of reaching a target audience. Alex Simonson and Bernd H. Schmitt have this to say on the topic:
“Consumers are bombarded with hundreds of visual and verbal identity elements everyday…and since they cannot possibly notice and pay attention to all the manifestations of a corporate or brand identity, they selectively choose to focus on some of them and ignore others. Consistent expressions increase the likelihood of remembering the expressed identities” (Simonson & Schmitt, 1997)
Perhaps the best example of internal and functional consistency in modern times is website design. Recurring elements in many websites such a logos in the top left hand corners or the placement of site navigation has set up a short list of common conventions. When arriving at a new Web site “users need to determine where they are, what they can expect to accomplish, what controls are available, where the content is located, and what other sections and pages are available” (Horton, 2006) and consistent design across the whole web environment is the best way to achieve this.
Some argue that consistency in design is the wrong approach. Jared Spool argues that thinking about user knowledge is a more important issue and that being externally consistent is taking the easy way out. Either way, the power of consistency has been demonstrated time and time again.
Critto, A. (2000). Consistency: Being coherent. Lanham, Maryland: University Press of America.
Horton, S. (2006). Apply a consistent design. Retrieved from Universal usability: http://universalusability.com/access_by_design/page_layout/consistent.html
Lidwell, W., Holden, K., & Butler, J. (2010). Universal principles of design, revised and updated. Minneapolis, Minnesota: Rockport Publishers.
Simonson, A., & Schmitt, B. (1997). Marketing aesthetics: The strategic management of brands, identity, and image. New York, New York: Simon and Schuster.
Spool, J. (2005, September 15). Consistency in design is the wrong approach. Retrieved from User interface engineering: http://www.uie.com/brainsparks/2005/09/15/consistency-in-design-is-the-wrong-approach/