Qualities are related to features. ARROWS distinguishes between four types of qualities.

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• UI and Interaction qualities highlight usability and ergonomic criteria as well as aesthetic aspects. In Lyric, such qualities include: ‘Simple’, ‘Efficient’ or ‘Fashioned’.  Some UI and Interaction qualities can be objectively assessed (for instance, efficieny, error rate).

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• Inherent qualities result from the spirit of a feature or a concept. Inherent qualities can also be related to a company’s identity or culture. In the specific case of Lyric, ‘Smart’ represent an inherent quality because the thermostat was meant to be so. Inherent qualities can be hardly objectively measured.

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• Functional qualities are related to underlying processes sustaining the UI and the interaction (e.g., data computation, database access). For instance, in the case of Lyric, ‘Instantaneous’ could be part of functional qualities if changes requested remotely (from the mobile phone, for instance) are taken into account within a relative short period of time (e.g., 0,5s). All functional qualities should be objectively measurable.

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• Global qualities reveal characteristics of the interactive system considered as a whole (i.e., related to the global feature). Global qualities can be UI and Interaction-related, inherent, or functional. Because only stability of many features makes a whole system stable, ‘Stable’ is a global quality relevant in many cases including the specific one of Lyric. In another example, ‘Expensive’ could be considered as an inherent quality of Apple products since high cost seems to be part of the company's culture and contributes to the brand image (for ensuring high quality). However, since expensiveness is related to a product as a whole, ‘Expensive’ would be a global inherent quality.