I/L paths Versus default paths

I want to know if my following thought is correct: The default include paths have priority over the -I<path>. On the other hand, -L<path> has priority over default lib paths. Am I right?

I'm asking this because I read the following doc:
https://libcxx.llvm.org/docs/UsingLibcxx.html
which has the following advice:

-------------------- Pasting -------------------------------------------------------------
If you want to select an alternate installation of libc++ you can use the following options.

$ clang++ -std=c++11 -stdlib=libc++ -nostdinc++ \
          -I<libcxx-install-prefix>/include/c++/v1 \
          -L<libcxx-install-prefix>/lib \
          -Wl,-rpath,<libcxx-install-prefix>/lib \
          test.cpp