Huh, I hadn't made this connection, and it still may be a case of ad hoc ergo propter hoc. But they sure seem to go hand in hand.

I think the first team on which I ever experienced Agile– working on a CAD program–was quite good with documentation. Ever since then–about 8 years–it's been almost all bad. All my work since then has been on iOS, so I maybe difference in domains has something to do with it too.

I often say code should "document itself," but I guess what I really mean is that the code should be readable and understandable, without obfuscating elements like anonymous identifiers, single letter variables etc, or needing comments explaining _how_. Comments should explain higher-order ideas like _why_. But, no one part of code can document the whole _system_ to which it belongs, nor can e.g. Git commit logs (which I also highly value). For that, I absolutely need diagrams and technical writing.