Revealing mistake: As the truck tips to the left, the stunt driver is seen steering, and appears to be activating the ram to finish the stunt.
Continuity mistake: Indy swings on the vine, and his bag is on his hip. As he gets up on the plane, it disappears, but the strap is on his shoulder again in the cockpit.
Continuity mistake: While Indy is chased while running towards the plane, he is in an open field where Jack the pilot can perfectly see him, but when the angle changes Indy is suddenly next to a forest.
Continuity mistake: The huge rock rolls down to ground level, but when the angle changes it's back on a levelled position.
Continuity mistake: The position of the door through which Satipo escapes with the idol is inconsistent in every shot, sometimes it's higher, then almost closed, then back to open.
Continuity mistake: As Marion initiates the drinking challenge with Belloq, from the front she quickly tosses the drink back, tipping her head back then forward. From behind she repeats the motion.
Revealing mistake: When the thug with the blade sticking out his back is standing still, there is some kind of squared device on his back under his clothes, presumably to retract the fake blade to end the sequence.
Audio problem: In Marion's bar, she uses a burning log to knock one of the goons out. As his face changes, you hear "ow!" then he moans as he falls over. However, his mouth doesn't match any of the sounds.
Visible crew/equipment: At the beginning of the ark chase sequence, Indy jumps into a truck off a horse and fights the driver. He pushes the driver up against the door. At the bottom of the frame you can see the camera shadow. (01:23:35)
Continuity mistake: When Indy is shot in the arm in the car, there's no blood on the windscreen at first, but in the very next shot there is.
Audio problem: While Indy tries to escape from the Well of Souls a stick in his mouth falls on Marion, who starts to cry very loudly; however, her mouth doesn't move an inch.
Continuity mistake: After Marion's been thrown in the Well of Souls, a net and pair of sticks over the crate behind Belloq appear or disappear randomly between shots.
Continuity mistake: After the kids save Indy at the bar, he exits and there's a man on the right carrying a load on his shoulder. He appears and disappears randomly depending on the angle.
Continuity mistake: When Indy's crew is lifting the stone door to access the Well of Souls, big clouds of white smoke come out from every corner. A frame later, from a wider angle, they're gone.
Continuity mistake: About to grab the idol, Indy passes a stick over a pile of sand on the ground which has a leaf on the center. A frame later the leaf is on the left side.
Other mistake: In the opening scene Indiana is with horses and scouts. A few minutes later he is running for his life and in a few moments he's at a waiting plane. Why does he need scouts and horses for the cave is in walking distance from the plane and how did the scouts and horses get there?
Character mistake: Watch the extras playing the Cairo civilians walking around just before the big swordsman reveals himself to Indy. Several of them are just aimlessly walking back and forth as if they have no idea where to go.
Continuity mistake: The amount of dates change from shot to shot before they are poisoned.
Continuity mistake: At the market in Cairo just after one of the guys tries to kill Indy with a sword and misses, the shadow from the wall changes between shots.
Continuity mistake: When Indiana is fighting the bad guys at the market in Cairo, one of them kills another one with a sword instead of Indy - their position changes between shots.
Answer: Indy and Marcus Brody believed that the Ark needed to be studied. They certainly didn't want to put it back where it was found. They believed that the U.S. government would find the best archaeologists, researchers, and scientists in the world to study the Ark. They are both upset that instead, the government has decided to simply lock the Ark away. This is why Indy says "Fools. They don't know what they've got there." as he is leaving the building.
BaconIsMyBFF