Summary: Effective icons depend on recognizability and interpretation. Evaluate them with methods appropriate for your specific research questions
Icon Usability
Effective icons can increase usability by helping users understand and interpret available functionality. However, when poorly implemented, they harm usability and introduce confusion.
In Digital Icons That Work , I emphasize the importance of two variables that affect overall icon usability: icon recognizability and icon interpretation.
Icon recognizability is concerned with whether people can identify the shape or symbol that the icon depicts. (Does the star look like a star?)