When it comes to expressing an opinion about a film, everybody's a critic. However, not everybody can successfully translate their thoughts into an interesting, cohesive review. Writing an interesting film review involves preparation, critical viewing and creative writing.
Knowing the backgrounds of the individuals involved in the movie allows you to create interesting comparisons between the new film and previous work. For example, if you were to write a review of Black Swan (2010), it would be advantageous to take the time to first watch several of the previous filmed directed by Darren Aronofsky.