I think I will stick with the 10 principles of Dieter Rams: Good design is innovative Good design makes a product useful Good design is aesthetic Good design makes a product understandable Good design is unobtrusive Good design is honest Good design is long-lasting Good design is thorough down to the last detail Good design is environmentally-friendly Good design is as little design as possible
Good design is honest particularly catches my attention, because the design of many digital products is fundamentally about misleading the user - see for example Facebook, where users are kept in the complete dark as to why certain posts are shown to them and not others, what data about them is being collected/resold, etc.