This question was asked out of mostly curiosity.
I've just flashed a new SD card with Rasbian Stretch Lite and when I did, little did I know that Stretch Lite is very similar to Arch Linux Arm. And Arch Linux is all about being as minimal as possible.
So then, I found myself having a very long line of package installations. Too bad that when I tried to have three Terminals running
sudo apt-get install packagename at the same time Linux kept on telling me that "some other process has locked down sudo."
This is really just a general question: The simplified question would be as to why "you can't have more than one root terminal process running at once?" Think installing multiple software packages, like I tried to do.