Bad Beard of the Year

OK, it's a detail, but what possessed the make-up department to stick that housepainter's brush thing on Peter Capaldi's chin?

Even assuming they had decided to ignore the millions of people who know exactly what Charles I's beard looked like, and were going to be shouting at the screen, "WTF is THAT?", why would they decide to create a beard for him that was not only tatty and messy (and therefore quite wrong for the character) but blatantly didn't look real? I've seen better fake beards in a school play.