In a word, the show is put on in a million dollar manner. Pictures are cut in accordance with their character. Sometimes a picture is filmed in too slow a tempo and must be speeded up in the cutting. Different directors have different methods. Unless all directors are, so to speak, standardized and work mechanically at the same tempo, this difference will always exist.
Titles are another indication.
If an audience complains that titles are too long or short, it is because the picture is not being run at the proper speed. The length of titles is determined by the speed for which the picture is cut. Another thing which we must discount is the fact that, in productions with a highly popular star, the first run exhibitor will often project the picture at a higher rate of speed than is appropriate in order to get more people into the theatre. It stands to reason that, if there is no definite running speed indicated, the exhibitor must rely on his own judgment or that of his projectionist. He no doubt could easily determine the proper speed himself, if he had the time, but if the projectionist has the proper directions before him in black and white, he will be far more likely to follow them.