Terminology of lastUnsuccessfulBuild is unclear

How can the symlinks to successful and unsuccessful builds point to the same build?
lrwxrwxrwx 1 jenkins jenkins 4 Feb 5 10:47 lastFailedBuild -> 1014
lrwxrwxrwx 1 jenkins jenkins 2 Oct 7 14:56 lastStableBuild -> -1
lrwxrwxrwx 1 jenkins jenkins 4 Feb 6 18:42 lastSuccessfulBuild -> 1022
lrwxrwxrwx 1 jenkins jenkins 4 Feb 6 18:42 lastUnstableBuild -> 1022
lrwxrwxrwx 1 jenkins jenkins 4 Feb 6 18:42 lastUnsuccessfulBuild -> 1022

(Edit: ls was on wrong job dir)