Yeah that's what I was doing for almost 5 years before I found Ansible. Now I even don't bother to put a CD. I go to my VPS provider and add a VPS then add my key and run an ansible playbook, which installs whatever I want, the way I wanted it.

The thing with package managers is that it get's boring to do everything all over again for a large amount of servers. Also your brain memory does not have a reliable version control. You need to keep why and how you do certain stuff on your server somewhere else. First thing that comes to your mind is a shell script and people are already using something better ( ansible, puppet, etc. ). Now, with this article, I see that there is something even better than this.

It's not just about installing a few packages with the package manager. You have system specific configuration, ranging from services to users to file systems and more, sometimes at odds with the state of a security patched/updated machine at any point in time. The way you configured the state of a machine 12 months ago might not be reflected when you build, update, and configure a machine today. This disconnect between installs gets compounded when you have to randomly log in and make minor tweaks to keep up with your ever-changing application specs (tweaks which rarely get documented), causing you or your successor to scratch their head wondering what steps are missing compared to before when doing a new build. This gets even more complicated when you build large clusters meant to scale, and can't afford to spend the time it takes to individually configure each machine. Orchestration aims at fixing this by giving you a way to bring the state of a freshly installed machine to the correct state of your production environment in an (ideally) consistent and repeatable manner, which is the whole point of all these fancy new products we're seeing these days.

One reason is because there is more than one of you.

By using Puppet, I never have to read my colleagues custom setup script because store it there. By checking in everything to version control, I see who has done what by reading the changelog.

If you are only managing your own servers and keep a strict discipline you will see less of the benefits.