Factual error: When She-Hulk loses her grip on the elevator cable, she catches onto the structure on the walls, but Betty loses her grip and falls several floors before She-Hulk can fall after her. A couple of shots later, She-Hulk has already caught up with Betty, even though there wouldn't be enough distance for She-Hulk to have reached terminal velocity to catch up with Betty.
Other mistake: When Bruce Banner is loosening his bow tie, he says it's cutting off the circulation to his head. If you look closely, you can see that it was loosely wrapped around his neck to begin with.
Continuity mistake: When She-Hulk and Bruce's limo is approaching the building, you can see the car slowing to a stop. When the shot changes to inside the limo, you can tell by the light glares passing by the window behind Bruce that the limo is now moving faster.
Other mistake: The reporter in the opening scene mentions that the Chateau de Shae is 80 floors. The camera then pans up the entire length of the building, and you can see it is nowhere near 80 floors high. It's only roughly half that size.
Other mistake: When Lou Ferrigno is walking away from the reporter, his movement suggests that he is walking on a downward slope, even though he is on level ground. He also disappears into thin air just before he would have stepped out of view.
Factual error: When She-Hulk spikes the volleyball into the sand, it leaves a hole. Sand is so densely packed that at best, this would have left a small crater. (00:00:25)
Continuity mistake: When Hulk throws the robot at Dr. Doom, you can only see a green background behind Doom. When Doom gets back up, you can see a rock wall behind him. (00:04:42)
Factual error: She-Hulk stops the runaway truck by holding onto the back of it and letting her feet drag on the asphalt. Afterwards, her high heels are still intact. The friction from stopping the truck would have destroyed her shoes within seconds. (00:06:00)
Continuity mistake: When She-Hulk is hang-gliding towards the Hollywood sign, you can see the letter Y is unoccupied. When the shot changes, Hulk is suddenly sitting there. The font style of the letter Y also changes. (00:08:47)
Continuity mistake: Just before She-Hulk shoves the contract in the director's mouth, the clip at the top of it changes from black to white. (00:20:57)
Continuity mistake: When She-Hulk is suggesting she and Bruce go to Rodeo to go shopping, they leave footprints in the sand. When the camera angle changes to a wide aerial shot, their footprints have disappeared. (00:21:14)
Continuity mistake: When the director spits the contract out, it flies up in the air and then falls back to the ground. When the shot changes and he says "It always goes right to their heads," the contract falls from above and bounces off his head.
Other mistake: After Hulk re-enters the Earth's atmosphere, his pants are still intact. It's one thing for Bruce Banner's pants to stretch enough to remain in place when he turns into the Hulk. It's another for them to somehow not be burned off in re-entry.
Factual error: Dr. Doom traps Hulk on an asteroid and sends it hurtling towards the sun, which it reaches in a matter of minutes. The sun is around 93 million miles from the Earth. Even if the asteroid was traveling at one million mph, it would still take nearly 4 days to reach the sun, not merely a few minutes. The same mistake applies for Hulk returning to Earth within a few minutes.
Continuity mistake: When Dr. Doom first walks into the lab, his mouth is open. When the shot changes, his mouth is suddenly closed.
Other mistake: When we see Betty being surrounded by the ninjas reflected in the pupil of Bruce's eye, the reflection is not reversed. (00:02:08)
Other mistake: When the elder Tongzing and Tenzing walk through the bushes, they simply pass through them, the bushes don't react to them moving through. (00:18:50)
Deliberate mistake: The footage of sharks swimming past the base windows in pairs is immediately recycled twice. (00:09:34)
Continuity mistake: When Gabe Jones is requesting backup, in the wide shot, his brown hair is more golden in color. (00:14:45)
Continuity mistake: When Betty and Gabe Jones are talking in the end, there is a brick wall in the immediate background. A few shots later when Betty greets her father, the wall is nowhere to be seen and the room is considerably deeper. (00:20:15)
Answer: The Hulk is a giant brute who smashes everything in his path when he is angry. In Ang Lee's "Hulk," General Ross, played by Sam Elliot, explains it to his daughter.