Quentin Tarantino's movies are not modern movies, they are postmodern movies. "Postmodern" refers to movies that are possible on the basis of modern movies. Common methods in postmodern works include citation, reorganization, deconstruction, etc. The objects of citation, reorganization, and deconstruction are modern films. You can think of it as "hip-hop in movies". Commonly used methods for hip-hop music creation include sampling and remixing, which is to combine and reprocess the melody, rhythm, and even complete fragments of existing music works, and at the same time incorporate your own original parts to form a completely different version of the original work. New works. Previous music creations inevitably used previous motives, melodies, etc., but in hip-hop creation, "a part of someone else's work is directly used as an element (usually a small section that is repeated repeatedly), but the finished product is completely unique. "It takes on a new meaning" is very rare. In the field of film, Quentin was the first master of this creative technique. His films are filled with so many elements from other films that it's a joy to just find all the references, aside from the work itself. As far as I can see, the climax of this approach is in "Pulp Fiction" (I think it is called "street stall literature" more closely to the original meaning. A more appropriate name for Grindhouse is "Video Hall Movie") when Mia and Vincent go to Jack Rabbit Slim's The dance part. From the lens, music, scenes to characters and plot, there are countless references inside and outside, which is amazing. Back to the topic. Quentin's post-modern movies have many elements from old movies in every aspect, from plot, dialogue, character settings, scene layout, to lens use and soundtrack selection. This is his style. (Occasionally it goes a bit further, such as the entire story of "Reservoir Dogs") On the other hand, the purpose of a film score is to match the picture and achieve the creator's (emotional or intellectual) intention. If all old songs can be used to achieve the goal, and the copyright fee is not much (Quentin is also unique in this regard, "discovering" many excellent songs that were once ignored), there is no harm in not using original music.