apt-get autoremove does not remove all dependency

OS: Ubuntu-18.04.1
I have a condition where I install using command "apt-get install package_name" which installs the package along with all the dependencies.
Now, when I am trying to uninstall the same package using command "apt-get autoremove --purge package_name" which uninstalls most of the dependencies but not all.
When I try to uninstall package using aptitude command, it is working fine.
E.g. Uninstalling using apt-get autoremove uninstalls 51 dependencies (not removing all dependencies) but uninstalling using aptitude uninstalls 58 dependencies (which is correct).

Any idea where I am going wrong with apt-get autoremove command or any help.

TIA.

I use aptitude by default, but I'm also old school when it was just better. There has been many changes over the years. There are also lots of different opinions on the difference between the two, but this answer does sounds more like how I remember the differences.

“apt-get autoremove” is a standalone command that removes ‘orphaned’ auto-installed packages.
AFAIK using it in the way you have, doesn’t apply it to the dependencies of the package you are purging (as you might imagine), but simply runs it as well as the purge operation, and the result is probably dependant on the order things happen during the apt-get session. Does a subsequent ‘apt-get autoremove’ clean up the leftovers?

In contrast, aptitude, by default, removes dependencies as well (so long as they aren’t also depended on by other packages).
Also, it’s dependency resolution is considerably smarter than apt-get, but that could also be a disadvantage in some situations (e.g. dist-upgrades where apt-get is the recommended tool).

Brains, thanks for your input.
So, as per the link shared in my case of scenario, I would need to use aptitude.

What happens if aptitude repo link breaks as during uninstallation, I am installing aptitude first and then uninstalling.

Try

 apt-get purge [package name]

coolpul, i think post #3 is the answer and contains the explanation you're looking for.

that, plus discovering the full potential of apt, apt-get, aptitude. by reading the fabulous manual.

in other words, everything works fine, just a little differently.