Continuity mistake: When K is looking at the tree in Sapper Morton's garden, he has a cut on his eyelid. Just after K moves the soil on the root of the tree to reveal the 6 10 21 marking, the cut has disappeared. K then has a flashback to his implant memory, and the cut has suddenly reappeared. (00:48:30)
Continuity mistake: When K discovers the 6 10 21 marking on the root of the tree, the scene cuts to a wide shot where his car is shown parked to the right of the tree. When K walks back to the car, the car is suddenly parked to the left of the tree. (00:49:05)
Continuity mistake: After discovering the 6 10 21 marking on the tree, K starts to walk back to his car. In the next shot, the fire coming from Sapper Morton's house is suddenly reflected on the side of K's car. (00:49:15)
Continuity mistake: When Luv strikes Coco on the back of the neck, on the floor he is bleeding from his nostrils, a tear streak of blood is shown coming from his eye, and has blood spewing from his mouth. There is a shot of Luv for a few seconds in between these two shots, but the amount of blood that Coco is shown producing appears far too quickly for just a few seconds. (00:49:55)
Continuity mistake: When Lieutenant Joshi walks into K's apartment to ask him what he has, she picks up a sock on the table which she puts back down. A couple minutes later, when she goes to leave the apartment, the sock has disappeared from the table. (00:50:25 - 00:54:00)
Continuity mistake: When K is in the DNA archive, he has the emanator for Joi on the desk in front of him. The emanator changes position between the shot where he asks for children born on 6/10/21 and the shot where he switches the emanator on. (00:54:30)
Continuity mistake: When Joi projects a holographic version of the wooden horse from K's memory, she flips it over revealing the date on the bottom, but when K goes to lower her hand, the horse is suddenly face up again. (00:56:25)
Continuity mistake: When K is talking with Joi in the DNA archive, Joi passes through K and places her left hand on his left shoulder, and leaves her right hand off his right shoulder. The shot changes angles and she suddenly has her right hand placed on his right shoulder. (00:56:45)
Continuity mistake: When K is cornered by the scavengers, he gets out of the car after they cut the door open. In the shot of one of the scavengers running up to K to attack him, nothing is hanging out of the car door. K then breaks the scavenger's back with his knee and the seat belt is suddenly hanging out of the door. (01:02:45)
Continuity mistake: When K is getting out of his car after the scavengers break the door open, he struggles to stand, holding onto the side of the car. One of the scavengers then runs up to K, next to the car. K then fights back and he is suddenly standing upright, several meters away from the car. (01:02:45)
Continuity mistake: When K is ambushed by the scavengers, the first one attacks him and K breaks his back with his knee. A second one then attacks him and K drops the first. When the first is dropped, the body is positioned near the car. Seconds later, when K is blasted back by an explosion, the first scavenger that attacked K has moved more ahead of the car. Also, when Luv is shown watching K from her perspective, the first scavenger's body has now moved again, several meters away from the car. (01:02:50 - 01:03:50)
Continuity mistake: When K is fighting off the scavengers in the scrap yard, he shoots at a few and keeps his gun pointed at them. When he says "stay back", he has his gun pointed forwards in one shot, then pointed to the right in the following shot. (01:02:55)
Continuity mistake: When K fires at the scavengers in the scrap yard, he keeps his gun pointed at them and an additional group of scavengers runs over a hill in the background. The shot cuts to an angle behind K, with his arm lowered, but in the next shot, his arm is suddenly raised and aiming again. (01:03:00)
Continuity mistake: When Luv is having her fingernails done in her office, the wide shot shows her hand placed on a rest, with her fingertips touching the edge of the rest. It then cuts to a close-up of her hand where her fingers are now going over the edge of the hand rest. (01:03:40)
Continuity mistake: After Luv fires the missiles on the scavengers, K gets up, goes over to the car and reaches inside the activate the drone. When he puts his hand inside the car, he turns his head to the right, but in the next shot, his head is facing the car. (01:04:30)
Continuity mistake: Whilst K is being walked through the orphanage by Mister Cotton, he stops when he recognises an area from his dream. In a shot from behind him, he is shown turning his head to the left to look at the area, but when the camera cuts to a different angle of him, he is looking straight forward, and then turns his head to the left a second time. (01:09:00)
Continuity mistake: When K takes the book listing the children at the orphanage off Mister Cotton, the book is open around the middle page where some pages are torn out. K then starts turning over pages leaving more pages on the right hand side than the left side. After Mister Cotton leaves the room, it then cuts back and the book is now suddenly back to being open around the middle of the book. (01:10:00)
Continuity mistake: When K and his girlfriend are talking about a real boy name for the protagonist, as the camera cuts from one character's face to the other's Ryan Gosling's hands are holding up his chin in some scenes and in others they aren't. (01:15:00)
Continuity mistake: K is shown to have a very thick stubble beard throughout the movie, but when he returns to the LAPD for his second baseline test, it is notably thinner than before. (01:16:35 - 01:23:05)
Continuity mistake: When Dr. Stelline begins designing a memory of a birthday party, after inserting the table and birthday cake, she inserts the birthday girl, followed by two other girls standing beside her, then rotates the table to insert a third girl standing at a different corner of the table, but in the next shot, the third girl standing at the different corner is suddenly standing visibly closer to the other girls. (01:18:05)
Answer: Think of any manufacturing process. Samples of new products are frequently created and then immediately destroyed. Also, the new replicant would require processing, training, etc. It was simpler for him to just dispose of the test.