Routine is not loaded until it is called. All routines are kept on disk in a re-locatable load format. The main program is loaded into memory & is execute
Dynamic loading means loading the library (or any other binary for that matter) into the memory during load or run-time.
Dynamic loading can be imagined to be similar to plugins , that is an exe can actually execute before the dynamic loading happens(The dynamic loading for example can be created using LoadLibrary call in C or C++)
Dynamic linking refers to the linking that is done during load or run-time and not when the exe is created.
In case of dynamic linking the linker while creating the exe does minimal work.For the dynamic linker to work it actually has to load the libraries too.Hence it's also called linking loader.
Hence the sentences you refer may make sense but they are still quite ambiguous as we cannot infer the context in which it is referring in.Can you inform us where did you find these lines and at what context is the author talking about?