not neccessary. Some in fact prefer fresh graduates 
. Maybe a fresh grad's mind is not as polluted compared
to one with working exp or an old bird aka la jiao. Fresh grad may
have the fighting spirit in striving at work which some old bird
don't have. And some old birds have very stuborn mindsets that are
not easy to change.
on the contrary, some prefer and even prefer those with relevant
working experiences is because maybe the job itself is a very
fast-moving job in a very hectic environment that 100% cannot
exceed deadlines and cannot afford any delays (etc procurements,
import / export, shipping, logistics etc), the employer may not
have time to train the entry level employee, and cannot afford any
delay.
