Visible crew/equipment: As the Oracle stands up from the bench, right at the end (after she says "Someday"), you can see a strip of yellow tape on the back of the bench marking the right place for her to sit. (01:54:40)
Continuity mistake: Sati and her family leave one suitcase when they get on the train (the one Neo was carrying), but when the train comes back and Trinity steps out, there is no suitcase. It can't have gone anywhere - as we see when Neo tries, the only way out is on the train, otherwise you're caught in a loop. (00:14:05 - 00:24:00)
Continuity mistake: In the scene where Neo sees the oracle at her home, as the shots go back and forth during the dialog immediately after she sits down, her cigarette pack goes from closed to slightly open several times, until she takes a cigarette, then it stays slightly open. (00:25:00)
Continuity mistake: When Trinity dies, the blood behind Neo's right ear keeps appearing and disappearing between shots.
Continuity mistake: At the beginning of the movie when Trinity and Morpheus first go to visit the Oracle, if you look behind them there are two wooden frames that are on the back wall where Seraph is, then a few shots later they are on the wall where Trinity and Morpheus walked in. (00:04:55 - 00:05:30)
Continuity mistake: At the very end when Oracle is sitting on a park bench, she and Sati look at the sunrise between some skyscrapers. About a minute later, there is another shot of the sunrise, but in this shot the skyscrapers are considerably shorter.
Continuity mistake: In the middle of the film when the captains and crews of both ships are discussing routes, the first shot we see Niobe. Behind her there is a guy at the side of her with a grey like t-shirt or jumper. The following shot he is standing behind her. (00:42:05)
Revealing mistake: In the scene where Captain Mifune is defending a bridge, alone, and commands "reload", he put the right arm of the APU straight, revealing in the background some sparks that floats independent of the action and stops for a few moments.
Continuity mistake: Close to the end of the film when some of the people from Zion are trying to blow the legs off of the diggers, in one particular shot you can see that they only load the right side of the rocket launcher, but in the next shot both sides are loaded. (01:03:00)
Continuity mistake: In the scene where Neo is talking with the Oracle in her apartment, the Oracle sits down at the table, picks up a bracelet, and right before the shot changes, you can see that it is on her hand, almost to the thumb area. When we cut back to her a second later, the bracelet is back on the table, and she picks it up and puts it on again. (00:26:10)
Continuity mistake: Just after Neo has seen the Oracle he is jacked out Trinity says "How are you feeling, are you alright?", her hand is on Neo's shoulder. The following shot her hand is on his back, then back to his shoulder. (00:29:10)
Revealing mistake: When Smith goes to see the Oracle and he puts two of his fingers inside her forearm, if you pay attention, there is a circle where the green effects start, they don't start from inside. (00:33:25)
Visible crew/equipment: In the scene where The Oracle is talking to Trinity and Morpheus, you can see the stage lights in the glasses worn by Morpheus. (00:06:40)
Revealing mistake: During the battle of the dock, just before Shara takes her second shot at the digger, she is seen from behind as her weapon is being loaded. As Zee is about to slide the rocket in, the green screen is momentarily visible through the barrel. (01:05:35)
Continuity mistake: In the scene where Bane has the scalpel to Trinity's neck, the bloody mark below it keeps disappearing and reappearing. The scalpel changes positions too as well as the blade itself changes. (00:52:55)
Continuity mistake: When Trinity is meeting with the Frenchman, the olive in his martini changes. In the first close-up shot, he only has one green olive on the cocktail stick. From then on he has two, until he eats one. (00:19:50)
Continuity mistake: As everyone is saying their goodbyes before entering the ships to go off to war, Neo's interface sockets on his spine keep appearing and disappearing during angle changes. (00:48:00 - 00:49:40)
Revealing mistake: In the subway scene, when Neo gets slammed towards the wall (and crashes into it) it's visibly Keanu's stunt double.
Continuity mistake: Towards the beginning of the Super Burly Brawl scene (right after Agent Smith gets knocked down on the road), Agent Smith and Neo fly up in the air and collide with each other, causing a massive surge of water to spread out as if a bomb went off. The water then falls back down on the Agent Smith clones, who are now looking up. But if you pay close attention it seems like they are completely dry, despite the fact that they have been standing in the rain and are all soaked. (01:43:50)
Continuity mistake: As the three start to fight at the Merovingian's club: after Trinity snaps there is a shot of Seraph pushing someone down as the man in black pulls the gun on him. To the right, there is a guy who is hurled to the floor by Trinity. In the next shot, Trinity hurls the man again. (00:21:30)
Answer: They never wanted to have the possibility of it getting set off accidentally, as it would render the entire dock area (and possible more) inert instantly. In fact, they probably weren't terribly prepared for the Sentinels ever to find/reach their location. In 100 years, they hadn't yet.
Rooster of Doom