SVN and Dolphin

Why the local folder’s icon for KDESVN contrlled directory is the same icon for other folders in Dolphin?
Thank you in advance.

Probably because your current icon theme does not have a separate icon for SVN folders.

My ignorance and I want to learn.

What is the difference between “KDESVN contrlled directory” and “other folders” (I guess you mean “other directories”)?
I do mean this of cource from the viewpoint of the file system, not from the viewpoint of the human knowledge that the contents of a particular directory is for a special purpose.