Part of it is due to the very story behind West Side Story, which made it possible for much creativity for both the Broadway stage production (i. e. the original, as well as many other stage productions of West Side Story, and the movie version, as well.
Part of West Side Story's being such a great piece of art is due to the fact that the intensely brilliant Leonard Bernstein musical score is so enticing that it lures people right into the cocoon of its brilliance, taking them right in, creating a cool event for the ears. It has enabled many different orchestras to play the score live, along with the film version, during many road shows, a couple of which I was fortunate enough to see and hear; last summer in Tanglewood (the summer home of the Boston Symphony Orchestra), and at Boston's Symphony Hall, last February. Having always wanted to see the film West Side Story on Valentine's Day, I ultimately got my wish, attended all three performances on Valentine's Day Weekend, and had a wonderful time, in all instances, if one gets the drift.
Stage productions of West Side Story, starting from the original Broadway stage production of this great musical, have allowed for much creativity regarding not only the scenery, but the costumes of the characters as well, ranging from very subtle scenery and very casual costuming of the various characters (especially the Jets, the Sharks and their girls.), which leaves much to people's imaginations, to very, very fancy and colorful. It can be fun to see the kind of artistic creations that revolve around such a great musical, with such a strong story that it allows for a very wide range of creativeness. and for people's imaginations to run wild.
As for the film version of West Side Story, it, too, is a fabulous work of art, which is one of the things that causes this great movie/musical classic to tug at my heartstrings in such a way that I never get tired of seeing it over and over and over again. The dancing, the richly-colored costumes and cinematography, the brilliant Bernstein musical score, and the scenery, both outdoors and on the big sound stage, are still intense to behold. West Side Story is one of the older classic films that has been re-mastered, cleaned up, reprinted, and digitally restored into a high-definition version, restored to its former glory. It's wonderful to see a pristine version of such a great film. Since I have written about the film West Side Story in separate posts here on this website, I won't go into any more details, but I'll add this: Although seeing West Side Story looks a bit more 3-dimensional on regular 35-mm film (there's no more printing of 35mm films.), the digitally-restored, Hi-Definition version of this wonderful film is fabulous, also.
When I first saw the film West Side Story around Christmastime of 1968, as a high school senior, I fell in love with this film immediately. Being a teenager still in high school at the time, I identified with the Jets, the Sharks and their girls regarding kids being kids, and so on, but it wasn't until I got a little bit older, and began seeing the film West Side Story in independent movie theatres, as well as attending art school, that I began to really appreciate this great classic film for the great work of art that it really is. It's a feast for the ears, the eyes, the emotions, and the heart.