I think it depends on the individual dog. Some are hairier than others. The problem occurs when the natural secretions from the ear get blocked by the hair and instead of coming out of the ear they stay in and become a source of infection.
It's fairly easy to keep it up once it's done, but for some first timers, it may be worth having the vet or the groomer do a thorough job one time and then you do the maintenance plucking thereafter.
