There are currently nine reviewers here. We have two editors who edit the reviews and post them. We are all bibliophiles, but have found in the last decade that most fiction put out by the main publishers is veritable garbage. Most fiction put out by indie authors is either plagiarized (which Amazon encourages), poorly written, or includes such graphic sex/violence it’s repulsive. So we look for wonderful plots elsewhere including in film.
Some novels and films are beautifully plotted. It’s difficult to explain how beautiful they are without describing and including the entire plot. So sometimes we include the entire plot. We don’t include every little detail, but the major plot points are usually there. We note the pacing, dialogue, plot holes, etc. just like we would with a novel. We also like to point out the great films and novels that Amazon reviewers (IMDB, Goodreads, Rotten Tomatoes) have panned for no apparent reason except maybe jealousy.
This is why we sometimes include the entire plot.