Because, Sometimes you need a Remote GUI.
I like RDP, it's familiar. I've used it forever. It has it's strengths, like ease of setup, and familiarity. It also has some weaknesses if not configured securely. As you can see by how short this lab is, that it's pretty simple to get up and running. That's just what I'm looking for in my lab environment!
Set it up and explore it's options. Use it as a target for your security lab, and see how results differ when what options are set.
Open a terminal connection, type: sudo apt-get install xrdp vnc4server
Replace vnc4server, if you have a different VNC server of choice.
Type Y to continue
Once the installation is complete reboot by typing: sudo reboot
Explore and Enjoy!