Whether a piece of furniture, a digital product or software: good design must be understandable. It should provide orientation, reduce complexity and make things feel intuitive and natural to use.
To me, logical thinking and visuality are inseparable. No matter how technologically capable an application may be, if people do not intuitively understand how it works, I do not consider it truly well designed.
That is why I engage as deeply with proportions, materials and typography as I do with user guidance, interfaces, processes and the question of how complex technology can become a simple experience.