* Limited-Time Events: Legendary Pokémon in Pokémon GO are usually only available during specific events, like raids, special research tasks, or community days. They aren't part of the regular spawn pool like common Pokémon.
* Rarity and Difficulty: Legendary Pokémon are extremely rare and challenging to catch, even during events. They are meant to be special encounters that require effort and coordination, making them a coveted prize for trainers.
* Game Balance: If Legendary Pokémon were readily available on the map, it would drastically imbalance the game. The strength and abilities of these Pokémon would make them overpowered in battles and make it significantly easier to progress, diminishing the challenge and fun for players.
* Special Encounters: Niantic, the developers of Pokémon GO, want to encourage players to engage in special events and activities to find Legendary Pokémon. This creates a sense of excitement and community.
In short: Legendary Pokémon are carefully managed by Niantic to ensure a fair and engaging gameplay experience. They are not meant to be found on the regular map, and they are made available during special events to create excitement and reward players for their efforts.