After using Macs for about two years, I've become accustomed to the painless installation process there: open the dmg, drag the app to the Applications folder, and you're done. Unfortunately, I recently had to install Acrobat Reader to electronically sign some insurance documents. They have managed to come up with a downright pathological installation process:
This is amazing. When I saw the very first pkg file, I was annoyed: I hate installers and they're rare in the Mac world. As I kept installing and installing, it was almost surreal. In the above list, there are three times where something is being installed. Working back from Acrobat itself,
So, while most Mac programs have shed the archaic notion of an installer altogether, Adobe Acrobat Reader has a program that installs a program that installs a program that installs the software you actually need.