Many software and product designers go gaga over icons and symbols, believing them to be the panacea of cool visual aesthetics and language-independent design.
Nothing could be further from the truth—symbols should be used sparingly, with good cause, only if well-designed according to established rules and conventions, and even then only once when their understanding has been properly evaluated.
The major issues that you must be aware of include:
- Location of icons is memorized faster and better than the image
- I’ve known this for a while, but have not been able to track down any academic studies. For the details of a study done by one UX design firm, see Old News about Icons.
- Icons are not always better than text
- Especially when the symbols and icons are not commonly known, enhancing their usability with a text label can increase their speed, accuracy, and usability for novices, and perhaps experts. See: The Importance of Labels, Effects of icon design on human-computer interaction, and The use of icons and labels in an end user application program. The latter paper also provides references to several studies that tout the benefits of symbols and icons may provide over text. Most importantly, it shows why icon-only interfaces are hard to use.
- Artistic flair is irrelevant
- Symbols should be designed with consideration of ambiguity, uniqueness, and dominance, rather than artistic values, as their overarching goal (while following established rules and conventions, of course). See Effects of training and representational characteristics in icon design for the research behind this.