You've Been Disconnected - S2-E17
Character mistake: Upon learning after the storm that the telephone cable was washed back out to sea, the Professor mentions the cable will eventually corrode and break and the Skipper says then a repair crew will have to come out and fix the cable so they'll be rescued. How? The cable is out to sea and a repair crew would never even get to the island since the cable's not there.
Gilligan's Living Doll - S2-E21
Other mistake: When the Howells give their suggestions, if you look at the dark rectangle, you can see the word REJECT before it lights up. Likewise, when Ginger talks to it, you see TILT before it lights up.
Gilligan's Living Doll - S2-E21
Revealing mistake: Watch the window on the barrel used as a washer. It looks to be somebody inside wiping the glass to simulate clothes washing.
Gilligan's Living Doll - S2-E21
Audio problem: As the Skipper is talking about respect, watch his lips. You can see him say boat, but you hear ship.
Other mistake: When Gilligan and the ape are staring at each other, with the idea that the ape will stay hypnotized and ignore everything else, look closely at the ape's eyes. The actor in the suit glances twice and the Skipper and Professor as they pass.
Ship Ahoax - S2-E23
Continuity mistake: The Professor is under the table which has a cloth positioned so he can't be seen. However, in the shots of him, you can see the background, and nobody's feet or the cloth.
Ship Ahoax - S2-E23
Continuity mistake: When Ginger holds up the Three of Clubs, her fingers are covering the bottom Club on the card. When the shot cuts to her in close up, her fingers are behind the card, with her thumb partially covering the bottom 3.
Other mistake: Mary Ann comes up to the Skipper while he's learning to juggle. If you look closely, the coconut bounces on the ground a couple of inches from his left foot. When Gilligan approaches, the coconut bounces off the bottom shelf. And in both times, the Skipper reacted in pain.
Other mistake: When Mrs. Howell looks at the lion in the mirror, the image is not reversed as it should be when the camera looks directly at the lion.
Operation: Steam Heat - S2-E25
Revealing mistake: After Gilligan says his line about the earth swallowing them all up, an explosion rocks the area. Between the end of the line, and the rocking, there's a split second of blackness indicating a cut between the line and the action.
Operation: Steam Heat - S2-E25
Continuity mistake: When Howell is talking to Gilligan, the ground apparently trembles due to a volcano. Before the rumble, Howell's Safari hat brim is bent up on the left side. After the cut to the Professor, the right side is bent upward.
Operation: Steam Heat - S2-E25
Revealing mistake: When Gilligan and Ginger are in the cave at the volcano, you can see that the steam in the two passageway openings behind them is being shot in from jet nozzles.
Operation: Steam Heat - S2-E25
Continuity mistake: The professor wound the clock on the bomb by turning the hand to nine. A second after it was tossed in, it reads eight. It then takes about about fifteen seconds between the numbers to get to zero.
Operation: Steam Heat - S2-E25
Continuity mistake: As Thurston tosses a packet of money away, his arm goes full circle, before his hand rests by his mid section. When the camera cuts, his right hand is over the edge at his wrist.
Will the Real Mr. Howell Please Stand Up? - S2-E26
Revealing mistake: When Gilligan demonstrates his man-made wings, when the camera goes close up to him, you can see the wires.
Continuity mistake: When Skipper tries on the sheet to teach Gilligan not to be scared, we see him putting it on and it is solid white. However, when Gilligan says he isn't scared he says it is because a "ghost doesn't wear a sheet that says S.S. Minnow on it." Now the sheet has wording on it. (00:08:45)
Other mistake: All of their sheets were the same type. The sheet that the "Ghost" supposedly took from them was more silken, not the regular knit.
Revealing mistake: After Gilligan lies down on his hammock, there is an "X" in the sand where actor Alan Hale, Jr. stands. Obviously it is the mark where Hale is supposed to stand, and he does stand there as he speaks to Bob Denver.
Visible crew/equipment: Outside the Howell's hut as the castaways ready to leave the island, the shadow of a boom mike enters the upper left side of the scene twice.
Visible crew/equipment: As the flame is blown out by Skipper's sneeze from behind a board held by Gilligan, you can just see a man from Skipper's left blowing it out.
Answer: Bob Denver answered this when he was on a talk show hosted by Pat Sajak. He said they were going to write into an episode where the castaways found all these clothes, but it got too complicated, so he said, they decided, "who cares, it's only a TV show," and forgot about it. So the writers and actors even asked this, they just never bothered to address it.