Revealing mistake: When Hulk jumps out of the river towards the New York skyline, he disappears into thin air.
Other mistake: When the forklift driver gets distracted by She-Hulk and crashes into the stack of metal vials full of flammable liquid, Bruce and She-Hulk don't hear any of the commotion until the explosion happens, even though they are only a few yards away. The crash and the falling metal vials should have been loud enough to alert them.
Other mistake: When Bruce Banner is sitting on the dock and recording his thoughts on a tape recorder, you can see that while his reflection's mouth is moving, his actual jaw is not.
Continuity mistake: When the government employee hands Betty the federal document, the federal seal disappears. (00:01:58)
Continuity mistake: The steel beam that Hulk pries off the top of the bridge and throws at Thor wasn't there when he first landed. (00:06:00)
Continuity mistake: The cable Thor tears off from the suspension bridge to wrap around the Hulk changes from a copper color to silver. (00:06:25)
Continuity mistake: After Hulk breaks free of the cable Thor wrapped around him, he lands on the street and is hit by a car, which damages its bumper and windshield. When the shot changes the car is suddenly pristine until Thor lands on its hood. (00:06:35)
Continuity mistake: When Abomination attacks Bruce Banner at the infirmary, he shoots him with a laser blast that leaves a hole in his shirt's chest area. In the next scene after Banner has been taken to Gargoyle's lair, his shirt is no longer damaged. (00:12:45 - 00:13:45)
Continuity mistake: When Gargoyle is standing in the doorway of the hospital room bidding farewell to Banner, they are standing at a straight angle respective to each other. When the shot changes, Banner has moved several feet to the left. (00:20:17)
Continuity mistake: When Gargoyle and Abomination are looting the electronics store and Gargoyle notices Bruce Banner walking by, a display stand appears next to Gargoyle in a close-up shot that is not there in wide shots.
Factual error: When Hulk lands on top of Mount Rushmore, Teddy Roosevelt's glasses are missing.
Continuity mistake: When Dr. Blake is walking towards the phone, it is resting on its receiver. When the shot changes to him picking the phone up, it is suddenly on a piece of medical equipment.
Continuity mistake: When Betty is walking through the infirmary, she is walking past a bedridden man to his left. After he reaches out and grabs her by the arm, the shot changes and she is suddenly on his right.
Audio problem: When the government employee is saying "You are hereby ordered to accompany me to Detroit," his mouth and jaw are completely motionless.
And the Wind Cries... Wendigo - S1-E10
Other mistake: When General Ross is telling Hulk he will take care of Betty, he tells the Hulk he needs him to take care of the Wendigo. At this point in the episode, Ross doesn't know that the Wendigo is the creature that they are hunting.
Darkness and Light: Part 1 - S1-E11
Continuity mistake: When Hulk is smashing his fists against the cliff walls, he causes Doc Samson to fall off the cliff and into the river near Hulk's feet. A couple of shots later, Samson has disappeared from view and a boulder is there in his place. (00:02:20)
Darkness and Light: Part 1 - S1-E11
Other mistake: When Gabe Jones is observing Doc Samson and Hulk emerging from the cave system in his rear view mirror, you can see his car is moving forward, but the image in the mirror remains the same size. (00:11:10)
Darkness and Light: Part 1 - S1-E11
Continuity mistake: Just before Doc Samson tackles Talbot, Talbot fires his blaster, which hits the middle of a console. A couple of shots later, the blast mark is at the top of the console. Its size and shape change as well. In the wide shot it is nowhere to be seen. (00:14:00)
Darkness and Light: Part 1 - S1-E11
Continuity mistake: The nutrient bath container that separated Banner and Hulk was large enough for both to comfortably fit inside, but when Betty is trying to perform CPR on Banner, you can see an unconscious Hulk still in the container, and it is suddenly barely large enough for him alone to fit inside. The design of the container also changes. (00:14:20)
Darkness and Light: Part 1 - S1-E11
Continuity mistake: When the soldiers burst into the lab, Talbot is standing next to the Hulk. When the shot changes, Talbot is suddenly standing in front of his soldiers and ordering them to stand down. (00:14:50)
Answer: I believe it was mentioned in an issue of Wizard Magazine that the show was cancelled because of low ratings, and reportedly the show's creative shift in the second season had a part to play in the low ratings, as the changes alienated fans.
Phaneron ★