e2fsck exit code 1 is not failure
gnome-disk-utility 3.36.1 UDisks 2.8.4 (built against 2.8.4)
Used Disks as a graphical interface to repair an ext4 partition; the repair was successful, but Disks reported it as a failure because e2fsck returned exit code 1. But exit code 1 from e2fsck means "file system errors corrected", not failure; exit code 4 indicates that the file system had errors that were not fixed. Telling Disks to repair the filesystem a second time resulted in a report of success, presumably because e2fsck returned an exit code of 0 the second time.