Question

______ is measured by how well the product or service successfully serves its users purpose. viability quality performance reliability

Explanation:

To solve this, we analyze each option:

• Viability: Relates to the ability to survive or be feasible, not directly about serving user purpose.
• Quality: In the context of products/services, quality can be defined by how well it meets user needs/purpose.
• Performance: Often about how well a product functions in terms of speed, efficiency, etc., not solely about serving user purpose.
• Reliability: About consistency in performance over time, not about serving user purpose.

So the term that fits the description of being measured by how well a product/service serves its users' purpose is Quality.

Answer:

Quality