“Jamaica Inn” wasn't included simply because it is not currently rated high enough on sites like IMDB and Rotten Tomatoes. With the exception of my Honorable Mention, the films on my top tens are not chosen by my own personal preference. “Jamaica Inn” is one of Hitchcock’s lesser-known works and a very early appearance for Maureen so, just as you have only recently discovered the film, most likely many others have yet to become aware of it. That might account for its current lack of popularity. Although I could have chosen to include it as my Honorable Mention, honestly, I felt that it would be a crime not to include “The Parent Trap” since it is such a classic family film (and one of my favorites growing up).