You’re looking for rational explanations? This is TV!
Here’s my pet idiocy-- from a James Bond book and movie, no less.
In “Thunderball” Emilio Largo’s bat, the Disco Volante, is a hydrofoil craft – the hull lifts out f the water at high speeds, and the craft “flies” on a pair of “wings” (A lot less drag, so it can go a lot faster and can go through ery shallow water).
BUT…
Largo also has a “secret” trap door in the bottom of the hull. No, I don’t care how wel you’ve tried to cover it up, that trapdoor is going to show up when the hull comes up out of the water. So Largo has a very fast boat, outfitted with hydrofoil outriggers that he can’t use, because it would give away his secret. You’d think eople ould get a little suspicious:
“Hey, Largo, can you take us for a spin in your hydrofoil?”
“Ehh, no. It’-a being repaired. Perhaps another time.”
“But you said that Last week.”
This problem is in both the movie and the book. Years later they remade it as “Never Say Never Again”, and the underwater hatch is still there, more visible than ever. But the “Flying Saucer” isn’t a hydrofoil this time.