I write long wordy emails with pictures all the time. The truth is, it's not for the recipient, it's actually for me, in 7 months time when I forgot that client ever existed and they pop back up wanting XYZ and I need to remember what we did last time.

The pictures and diagrams are for me.

[–] [email protected] 7 points 2 days ago

I also take lots of notes and document my work, but I use OneNote or a wiki, and keep files and records in organized directories. I know people do what you describe and then email retention policy changes and suddenly all of that information is subject to deletion without their input and they have to scramble to copy all of it, if that is even allowed.