Note that Beginners have no previous contact with the phonological and graphical system of language. Meaningful tasks only. There's a need to observe Ss' wishes to some extent.
Pedagogical purpose is just as valid as others.
Ss' writing often fails in the area of logic. They may be able to write 2 grammatical accurate but non-sequitor sentences. Coherence as well as cohesion. In future life - Postcards to old friends, booking holidays abroad, business letters. How we Teach Ss to write.