Design is by nature both holistic and ruthlessly simplifying
A theory is by its nature a partial account of reality—a set of blinders through which some aspects of the world are highlighted and others become invisible. Design is by nature both holistic and ruthlessly simplifying. A designed artifact, whether it is a piece of communications software or a city park, must address the complex mixture of human needs, embodied in a weave of physical and social interaction. But the design itself cannot embody all of these complexities if it is to be constructible and understandable. The design must embody a simplification,leaving room for the texture of the world to be filled in by the interpretation and practices of those who use it. (emphasis mine)
– Terry Winograd. 2006. Designing a New Foundation for Design. Communications of the ACM 49, 5 (May 2006), 71–74. DOI:https://doi.org/10.1145/1125944.1125978
I think about this quote a lot.