I downloaded the latest version or prince on a Mac. Followed the instructions and:

sudo ./install.sh
Prince 12.5

Install directory
This is the directory in which Prince 12.5 will be installed.
Press Enter to accept the default directory or enter an alternative.
[/usr/local]: /usr/local/lib

Installing Prince 12.5...
Creating directories...
Installing files...

Installation complete.
Thank you for choosing Prince 12.5, we hope you find it useful.
Please visit http://www.princexml.com for updates and development news.

When I look in the /usr/local/lib I was expecting to see a "prince12.5" directory but it's not there, but I do see a "bin" and a "lib".

I am running Mac OS Catalina, 10.15.

Thanks

Prince is following UNIX conventions here so the main shell script will be installed as /usr/local/bin/prince, then the rest of the installation is mostly under /usr/local/lib/prince.