Roomba

Early models of the Roomba robotic vacuum cleaner uses a chime when finished, and a secondary indicator light to show when it needs cleaning. The Roomba could inform without needing to speak in a human voice. A simple tone and light take less time to parse then the spoken word.

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IV. Technology should communicate, but it doesn’t need to speak.

Simple icons and color indicators work to communicate most information needs.

If voice is necessary, create responsive but not proactive interaction patterns to ensure the user is in control of when they engage.