käytettävyyskertoja

Käytettävyyskerroin is a Finnish term that translates to "usability multiplier" or "usability factor" in English. It refers to a conceptual metric used to quantify the impact of usability on the overall success of a product or system. The core idea is that a system with excellent usability can achieve significantly better results than a technically equivalent system with poor usability.

The käytettävyyskerroin is not a fixed, universally defined formula. Instead, it's a framework for thinking about how improvements in usability can lead to amplified benefits across various aspects. These benefits can include increased user satisfaction, higher task completion rates, reduced error rates, faster learning curves for new users, and ultimately, greater economic return on investment. For example, a product that is easy to use might attract more customers, retain them longer, and require less customer support, all contributing to a higher "multiplier" effect on its overall value.

While not a strictly measurable entity like a performance benchmark, the concept of käytettävyyskerroin encourages designers and developers to prioritize user experience. It emphasizes that investing in usability is not just about making things look good or feel intuitive; it's about directly influencing the practical effectiveness and commercial viability of a product. By considering this multiplier, teams can better justify the resources allocated to user research, interface design, and usability testing.