There’s an old maxim of user interface design about ensuring that products are useful, usable, and desirable. Does the design solve a problem? Can people make it solve their problems? Do people want it to solve their problems? But even if the answers to these questions are all “yes,” now what? “Usable” and “satisfied” are pretty low bars. It’s like saying your design is “adequate,” “fine,” or “average.” It’s like saying you’re having sustenance for dinner. People want more than that.