The kleopatra.exe process doesn't exit if the app is Quit.
I'm seeing this with a gpd build of gpg4win master (2afc7aadcf9f023d7d86b46a480e92bab69c4b83).
When pressing the Quit button Kleopatra logs
[6468] org.kde.pim.kleopatra: queryClose [6468] org.kde.pim.kleopatra: ReaderStatusThread[2nd]: new iteration command= "__quit__" ; nullSlot= true [6468] org.kde.pim.kleopatra: ~KUniqueService