Nice graphic design, usability, clarity, intuitive controls and speed. These are the key values for the right UI / UX product. However, there is much more to a great product than just what can be seen at first glance.
UI / UX also includes user surveys, design iterations, the right information architecture and selected technologies, interactive prototyping (LINK for prototyping), usability analysis and other services.
We always try to combine the above so that we create a design that is perfectly usable and meets the main goals of your business.