2. Pacing
This seems like something so vital to get right but too often horror films in general either blow their load early or just take an eternity to showcase an interesting scene. The Conjuring starts off introducing viewers to the Warrens subsequently introducing them to the rules of the film and presentation of paranormal investigation. The Conjuring then introduces us to the Perron family and from there slowly builds up atmosphere starting its scares off small. Clocks stopping at random yet specific times, sleepwalking, objects falling, etc. And then a dog dies unexpectedly soon. And then Carolyn starts receiving unexplainable bruises in her sleep. Pretty soon you have the Warrens involved which subsequently introduce the more mysterious aspects of why a mother sacrificed her child. The final 40 minutes take everything and enter all out terror mode complete with excellently choreographed scenes involving the Perron family sliding around the floor trying to stop an entity from dragging their daughter. Finally, the film reaches its logical of height of terror with an exorcism.