Movie twists make films more interesting by pushing the story in unexpected directions. Twists can include things like reversing the roles of a hero and villain, the revelation that characters are related or hidden motivations for a character. While some of these are genuinely unexpected shocks with no clues, others can be figured out by audiences if they pay close enough attention. Some big reveals were hiding in plain sight all along.
Source:https://www.cbr.com/movie-twists-that-are-obvious-if-you-just-pay-attention/