An impressive cinematic from Demon Seals shows how expensive the production of trailers is, how long it takes, and what purpose they serve.
The last piece is missing
In the last few decades, storytelling has become an incredibly important element of games. Understandably, because it allows players to emotionally engage with events and develop a greater interest in the game world and thus in the game itself, which can almost directly translate into financial gain for the developers. It makes perfect sense that a lot of money is spent on capturing the story when a greater success is anticipated from it.
Such investments often produce impressive trailers, as is the case with Demon Seals. The following trailer cost nearly 2 million dollars to produce:
From the initial planning to the completion of such a video, it takes 2 years in this case. This probably also explains why many studios can rarely respond to the request for “more cutscenes”, like in World of Warcraft, as the costs and duration of production are simply immense.