Cargo cult programming is like a game. Programmers do activities in a certain way without understanding why the activity is done that way. It's like making pretend airplanes out of sticks. Even though we all know the airplanes won't really fly, we play the game anyway.
A programmer might copy a certain piece of code without understanding why it works. This might fix a problem, but the programmer won't understand why the problem was fixed. Or a programmer might use a certain writing style for their code, even though it does nothing to make the code better, because that's how everyone else does it.
Cargo cult programming isn't a good thing. If a programmer doesn't understand why something works, they won't be able to fix it if it stops working or update it when something changes. It's better to understand why the code is written a certain way so they can improve it when needed.