EVERY lady holds one of the layback positions for at least 8 revolutions.
That statement is no more true than, say, "Every lady rotates double axels with good landings."
You probably haven't been watching enough lower-ranked seniors -- seniors who don't earn the minimum scores to qualify for Worlds -- let alone juniors, novices, etc. We expect the top seniors to do well on these skills, but the rules apply to all levels. And even the best skaters don't always succeed at what they attempt.