Originally Posted by exploretoi
I've seen some bottles that are marked as "low fill", so maybe that's the case.
There are gonna be times when the precise machines that measure the juice into the bottles run out of liquid. Then I imagine it is up to the quality department whether those partly filled bottles are sold as seconds or emptied, cleaned and put into another run. Companies that trade on the exclusiveness of their brand are probably not very interested in selling seconds. Other companies, and particularly fakes, may not be so squeamish about these things.
I expect there would not be many jurisdictions where selling short measures would be an acceptable practice under trade description laws.