Earlier quoted context omitted.
> communicate don't decorate Is another fantastic one. I'm really getting into the idea that design is basically all about guidance. Mapping a goal-worthy journey for the user. Which is why we use words like 'journey' and 'story' often when describing UX issues. Thanks for the comment and the link! Very enlightening.
Mentally, I add the prefix “communication” whenever I see references to (graphic) designers. It helps me keep what their ultimate responsibility should be in any software project: to communicate, as clearly as possible, within the chosen mediums of expression. https://en.wikipedia.org/wiki/Communication_design
Maintaining this perspective of what designers are in function will probably lead to better designers (via the form of their work) overall.