At https://musicbrainz.org/relationships , all “related/coordinate points” are filled & linked as if there were actually relationships for them, which is misleading. Currently, there are 20 dead-end links (of a total 91):
Area-Artist
Area-Place
Area-Release
Event-Genre
Event-Instrument
Genre-Recording
Genre-Release
Genre-Series
Genre-Work
Instrument-Place
Instrument-Recording
Instrument-Release
Instrument-Release group
Instrument-Series
Instrument-Work
Place-Release
Recording-Release
Release-Release
Release-Work
URL-URL

Unavailable relationship points should be displayed as such, not luring editors into dead-end clicking. Most intuitive way, keeping coordinate field filled intact for navigation, also communicating intent (≠ mistake) through visibly inactive links, would be to have the dead-end links greyed-out, and a text right on the page ~“Grey link: This relationship does not exist.” rather than having the links active (“Something here”) but dead-ending (“Nothing here”).