Never a prepossessing breed can look more ill-used than any other dog

[suprunp]

The puppies now would have made a suitable subject for an RSPCA poster. Never, at the best of times, a prepossessing breed, Bedlingtons can, in moments of crisis, look more ill-used than any other dog I know. They stood uttering quavering, high-pitched yelps like miniature sea-gulls, shivering violently, periodically squatting down bow-legged to decorate the platform with the results of their fear.
("Birds, Beasts, and Relatives" by Gerald Durrell)

Would you be so kind to explain to me what the author actually wanted to emphasise by the sentence in bold? (I can't quite put my finger on it.)

Thanks.

[Barb_D]

Never, at the best of times, a prepossessing breed, Bedlingtons can, in moments of crisis, look more ill-used than any other dog I know.
Bedlingtons aren't usually very attractive, even when they are at their best. When they are at their worst, they look worse than any other dogs, as though they had been abused.

(I have no opinions on Bedlingtons. I'm just saying what the writer said. Bedlington Terrier Information and Pictures, Bedlington Terriers)

[Hedwig]

Poor little things! They certainly are unprepossessing. It's the hair tuft on their muzzle. Those guys could certainly do with a more flattering haircut.