The diagram can also be a view into the thoughts and motivations behind the implementation. Which can help the next programmer know the design and why certain d

The diagram can also be a view into the thoughts and motivations behind the implementation. Which can help the next programmer know the design and why certain design decisions were made. But not everyone thinks about designs as 2-D pictures. I'd argue there's selection pressure that favors programmers being good spellers and symbol-manipulators. Some people find it intuitive to think of concepts as boxes and the relationships between those concepts as lines. Or maybe to think of a 2-D grid of actions/dependencies with deliverables on the vertical axis and work-steps on the horizontal. But not everyone likes these kinds of visualizations. Some prefer a text-based description. And some designs don't fit any obvious pictorial representation.