Makes you wonder how breeding works sometimes and how they can predict traits will go where and what not.
Breeding before was taking the dogs that were the best representation of te breed, temperament, intelligence, coat and healthwise. A bunch of factors taken into account to make sure the best puppies could come from the parents.
But when breeds got popular, this was forgon or brushed over in order to get the most puppies out quicker. Dogs that maybe weren't the most desirable were bred anyway, despite health problems. Leading to puppies having health problems. But then, say with the pug, people kept buying puppies with the double curled tail (which can lead to paralysis) and so breeders keep trying to make puppies like that because it's what sells. Then they end up with fat, wrinkley, double curled, genetic abominations.