When installing programs (e.g. openmpi, comsol, lammps) to /usr/local, usually a lot of separate files are created in /usr/local/bin, /usr/local/lib, /usr/local/src etc.
Now when I want to uninstall (e.g. for updating), then finding each relevant file separately would be a madness. Some programs (e.g. openmpi) provide the make uninstall
target to do this automatically, but the original makefile might not be available and finding it seems tedious.
Thus, until now I have resorted to building/installing stuff into /opt, where it makes a separate folder for each application and it usually suffices just to delete the folder to uninstall (or make separate folder for a newer version to update).
Of course, when installing to /opt, you have to manually set up paths, but usually this is easy.
Now, what is the appeal to installing to /usr/local compared to /opt? Is there an easy way to uninstall/update programs installed there?