Whatever "it" really is, I'm afraid "It" lacks it. Oh, I know a lot of people like the film, and I admit there are funny moments, but as a whole the film feels too much like an assembled piece. What's worst, it was! Paramount made this after writer Elinor Glyn said that Clara Bow had "it", a notion arguably best translated as sex-appeal. The studio was clearly trying to cash in on their increasingly popular star. Despite being obvious, in case you missed it not only the first title card reminds you of this, but the writer herself appears later on to explain the audience what "it" is. The problem is that sexiness, sex-appeal, "it" or whatever you prefer to call it, usually depends on the person's unawareness. This is actually mentioned by Glyn. The moment someone becomes conscious of it and try to recreate it, or even keep it, it's lost. Since this is the only film I have seen with Clara Bow, I can't say if she ever had "it", but in my opinion she doesn't have it here. Furthermore, she's not even a terribly good actress - when I look at other major female stars of the late 1920s, such as Gish, Garbo or Marion Davies she pales by comparison. She has a fun twinkle in her eyes and an engaging smile but you need more than that.
Of course it doesn't help that the film has a very thin plot. It's the story of a sales girl going after her boss, while keeping her good name despite appearances. If done five years later and by MGM this would be the typical Joan Crawford vehicle, the sort that almost killed Crawford's career. Because it was built around Bow's persona, the rest of the cast is almost as bland as it can be, just to make sure no one would steal the picture from her. I was expecting much more out of this, but considering the film's popularity then and even now, it might be that this is simply not tailored for my taste.
PS - It's worth keeping an eye open for a very young Gary Cooper as a reporter.