There are two tibetan translation of the word Hinayana - Thek-dman and Thek-chung.

dman = inferior. chung = small.

None of these, imply faultiness in its meaning. Faulty in Tibetan would be skyon.

The reason why Tibetan scholars would deny Hinayana path of being faulty is that, it's a true path leading to Nirvana. Hence, it's not and can't be faulty vehicle.

The sanskrit word Hina "हीन" has many meanings, and looking at the way Tibetan translators translated it, I'd say the sanskrit word Hinayana implies smaller/inferior vehicle. Not broken, not faulty.

The assignment of the label "inferior/smaller" is based in the motivation being self liberation.