These little audio visual preambles offer the on-screen equivalent to liminal space. In architecture theory, a liminal space is essentially a transition between one space and another. When you walk into a movie theater, you don’t actually walk directly from the parking lot, through a door, and into a room with seats and screens. First, you walk through the concourse, maybe buying some popcorn–which boosts the theater’s bottom line, okay. But the concourse also gives your mind a cleansing area, to shake off the stress of the day and prepare you to sit for two hours in a dark room. This is exactly the experience Netflix wants to create, just without the building or the popcorn.
Source: Why Netflix changed the intro to its original programming