Continuity mistake: El Presidente Luna stops moving and bleeds from his mouth with his palm against the floor. He's wide-eyed dead and motionless, but next time we see him after Harley stops musing over how well-endowed he was, his hand is turned around, palm up. (00:48:35)
Continuity mistake: When the valet tells Harley that the president wants to see her, the guard behind Harley is looking towards her. For her response, he's facing away from her, and her facial expression is different as well. (00:42:00)
Continuity mistake: Bloodsport is talking to his daughter about her crime. During the conversation, the continuity between shot and reverse gets jumpy at times; for instance when he mentions that she "dragged out the paternity test" Idris Elba stretches out his arm only to be still when his daughter screams at him. Later on he reminds her he told her to do 'her thing' and gesticulates with the right hand, but his arm is still and low in the next shot. (00:00:17 - 00:16:50)
Continuity mistake: Amanda Waller told Flag that they cannot retreat from the beach. Harley chirps "Okie dok" as a response; in the first shot she is putting her right hand on the weapon, but in the next she is out of focus in the foreground with the same hand on her earpiece. (00:09:15)
Continuity mistake: Once he reassured the crew about Weasel, Flag orders everyone to get in the position for the paradrop. He motions towards them bringing his hand down, which is operating a switch above him in the next shot. (00:05:55)
Continuity mistake: On the way to the airdrop, Blackguard asks the others "Is this thing a dog?" Next to him, TDK has his hand in his lap to a fist in one angle, palm down on his thigh in the next. (00:05:20)
Continuity mistake: Savant is taking a look at the rest of the team. The blonde Blackguard is goofing off with the guard closest to him as he shimmies. Closer angle, he puts his hand on the gun on his left PC. Next shot, and he's back swaying with both arms down. (00:02:40)
Continuity mistake: At the beginning of the movie, a goldfinch lands in the corner of the prison courtyard. There's a wet/mouldy area in the corner that is suddenly much smaller in the following close-up. (00:01:10)
Continuity mistake: When Peacemaker kills Rick Flag by stabbing him in the heart, the depth of the object changes between the close-up shot of Peacemaker's hand and the next shot, where we can see the part sticking out of Flag's chest has increased. This is before Peacemaker hits the object deeper. (01:31:05)
Continuity mistake: When Amanda Waller orders the blonde subordinate to "Open it", the digital clocks show the same times shown minutes earlier when they had yet to wake up, contact them, talk to them, order them to retreat, witness their change of mind. All of which certainly took longer than a minute. (01:46:45 - 01:49:35)
Continuity mistake: After Waller issued her order to leave Corto Maltese to its fate, Bloodsport turns his back to Starro that is wrecking the city and walks towards the camera. Just a moment before the cut, Margo Robbie is shrugging, a gesture that is supposed to happen in the next shot, and she in fact repeats it in the next shot a second later. (01:48:30)
Other mistake: Escaping from her captivity Harley kills a dozen people with the javelin in brutal gory ways, but when she gets on the taxi the weapon's golden finiments appear to be spotless. (01:14:00)
Continuity mistake: The Corto Maltese Army is storming the pleasure district. As the camera pans from the club doors to the incoming vehicles, to the far left there's a john wearing a brown suit posing one-handed in front of a girl. In the wide shot from behind the trucks, you can see that a soldier pushes the guy back to the wall. But as their commander gets off the hum-vee and yells to search everywhere, the guy is standing in the corner, and at the next cut he's back against the wall. (01:01:45)
Continuity mistake: Look at the overhead shot of the limo approaching the Presidential palace. The gates including the sandbags where military men are stationed are in the shade. We see then a valet open the door for Margot Robbie, and the spot is in the sun. (00:41:35)
Continuity mistake: When Harley bursts out in a Mario Kart-themed insult at the Cortomaltesians, the braid in front of her shoulder is the left one and not the right one. (00:41:00)
Other mistake: Beach scene; by the clocks in the control room it's supposed to be just before or at most past midnight (22:52 in Florida, presumably). Explosions nearby, barely past the thick of vegetation, but the team instantly goes to sleep as if they were anyplace safe. To make it more absurd, they awaken in the 'middle of the night' when Polka-Dot Man relieves himself and King Shark tries to eat the rat lady. Cut to the control room, and it's 23:53. It's as if they did not try to move any distance at all. (00:12:35 - 00:29:40)
Continuity mistake: When Amanda Waller powerpoints Gaius Grieves to the team, from behind she is holding the clicker shoulder-high. Her arm is more outstretched and raised in the wider angle. (00:23:25)
Other mistake: Bloodsport and the others see the explosions Harley is running from, which are less than a couple miles off. The beach itself should already be lit by the explosions and burning wreckage, which the team couldn't fail noticing as they were approaching. To make the distances more ludicrous, when we see Flag's signal in the control room it's said he's "1 mile north" of them, He's already halfway towards the western isthmus. No reason why it'd take them a whole day to make it to their destination.
Continuity mistake: Harley slaps the now dead Javelin in the face asking frantically about his incomplete dying words. Literally one moment her hand is on his cheek, the next is mid-length on the shaft of his weapon. (00:26:50)
Continuity mistake: Briefing scene, Ratcatcher 2 raises her hand to ask her question. Notice her right hand, open on top of her thigh. Close-up, and her hand is closed and to the inner side of the thigh. The hand is back in its original position when the first angle is used again. (00:23:45)
Answer: It's a combination of various reasons. Will Smith wasn't available to reprise his Deadshot role, so there was a shift in the story. King Shark was intended to be in the first film, but the CGI was too extensive, so they went with Killer Croc. In this film, they took the opportunity to bring in King Shark as the "monster" character. But, this film isn't really a sequel or reboot. Basically, this is a new storyline with new characters, and many of the previous characters are just not in the film, with no exposition on what happened to them, and they may not even be part of this film's "universe." The fact that some of the actors play the same character in both films only serves to muddle the concept of this film not really being a part of the previous film's continuity.
Bishop73