Here's why:
* Judgment is a move exclusive to certain Pokémon: It's a move primarily associated with the legendary bird Pokémon (Articuno, Zapdos, Moltres) and some other specific Pokémon.
* Moves are learned through various methods: Pokémon learn moves through leveling up, breeding, TMs/HMs, or specific events. Cheating, in this context, would imply bypassing these standard methods.
* Cheating isn't a game mechanic: The Pokémon games don't have an inherent system for "cheating" in the way you might think of it.
However...
While Magikarp cannot learn Judgment in a traditional playthrough, there might be ways to "cheat" it in through unofficial means:
* Game modifications: Tools like save editors or cheat codes could theoretically be used to add Judgment to Magikarp's movepool. This is not a standard practice and might be considered unethical by some players.
* Fan-made content: If you're playing in a modified ROM hack or a fan-made game, the creators might have changed the movepool rules, allowing Magikarp to learn Judgment.
Remember, altering the game's mechanics in this way is outside the intended design and might affect your online gameplay or other aspects of the game.