How do you balance naturalness and efficiency in voice user interfaces?

1 Understand your users and their context

The first step to balance naturalness and efficiency in VUIs is to understand your users and their context. Who are they, what are they trying to do, where and when are they using your VUI, and how do they prefer to communicate? These factors will influence the tone, style, and structure of your VUI. For example, if your users are busy professionals who need to book a flight quickly, you might want to use a more formal and direct VUI that asks only the essential questions and confirms the details. If your users are casual gamers who want to have fun with a trivia VUI, you might want to use a more friendly and playful VUI that adds some humor and feedback.

2 Follow the conversational maxims

The conversational maxims are a set of rules proposed by the philosopher Paul Grice to describe how people cooperate in natural conversations. They are: be relevant, be informative, be clear, and be polite. You can use these maxims as guidelines to design your VUIs that are natural and efficient. For example, be relevant by asking and answering questions that are related to the user's goal and context. Be informative by providing enough information but not too much or too little. Be clear by using simple and familiar words and phrases, avoiding ambiguity and jargon. Be polite by using appropriate greetings, feedback, and politeness markers, respecting the user's preferences and privacy.

3 Design for error and recovery

One of the biggest challenges of VUI design is dealing with errors and misunderstandings. Unlike graphical user interfaces (GUIs), VUIs do not have visual cues or feedback to help the user navigate and correct errors. Therefore, you need to design your VUIs to prevent, detect, and recover from errors gracefully and efficiently. For example, you can prevent errors by using clear and consistent prompts, confirming the user's input, and providing help and guidance. You can detect errors by using speech recognition and natural language understanding technologies, as well as user feedback and signals. You can recover from errors by apologizing, explaining the cause, offering alternatives, and repeating or rephrasing the question.

4 Optimize for multimodality

Another way to balance naturalness and efficiency in VUIs is to optimize for multimodality. Multimodality refers to the use of multiple modes of communication, such as speech, text, images, gestures, and touch, to enhance the user experience. Multimodal VUIs can leverage the strengths and compensate for the weaknesses of each mode, as well as provide more options and flexibility for the user. For example, you can use text or images to display complex or detailed information that is hard to convey by speech, or use gestures or touch to enable quick and intuitive actions that are cumbersome by speech.

5 Test and iterate

The final step to balance naturalness and efficiency in VUIs is to test and iterate. Testing your VUIs with real users is essential to evaluate how well they perform, how natural and efficient they are, and how satisfied and engaged the users are. You can use various methods and tools to test your VUIs, such as usability testing, wizard of oz testing, prototyping, analytics, and feedback. Based on the results, you can identify the strengths and weaknesses of your VUIs, and make improvements and refinements accordingly.

6 Here’s what else to consider

This is a space to share examples, stories, or insights that don’t fit into any of the previous sections. What else would you like to add?