In my experience I see a lot of architecture diagrams which make extensive use of FTP as a medium for linking architectural components.

As someone who doesn't make architectural decisions but tends to look at architecture diagrams could anyone explain what the value is of using FTP, where it's appropriate and when transferring data as files is a good idea.

I get that there are often legacy systems that just need to work that way - although any historical insight would be interesting too

I can see the attraction in transferring files (especially if that's what needs to be transferred) because of the simplicity and familiarity and wonder if the reasoning goes beyond this.