Comment # 2 on bug 996502 from Michael Andres

(In reply to Bug Reporter from comment #0)
> Another example, the list of dependencies to be removed is grossly
> incomplete:
> sudo zypper rm --clean-deps dolphin

According to the testcase only a small number of packages on your system is
flagged as 'autoinstalled' (i.e. automatically added by the dependency
resolver; see /var/lib/zypp/AutoInstalled). Only those packages are considered
for cleanup.

Packages not mentioned there are considered to be 'userinstalled' and won't be
cleaned automatically.