echo vs. cat

I have seen a lot of examples that use 'echo', i.e.,

   :0
   * condition
   | echo "first line of message" ; \
     echo "second ..." et cetera

I started out with spam.rc from "ariel"  which got me into the habit of

   :0
   * condition
   | cat file_containing_message

although I note that spam.rc did have one recipe using the echo method.

What are the reasons for choosing each method over the other?

I know one: it's MUCH easier to edit file_containing_message than
to edit <long recipe with lots of echoing>

What else (either way)?