Why do Game Boy Advance games have batteries?

Game Boy Advance games often have batteries to save player progress and game data, particularly for titles that feature extensive gameplay or complex mechanics. The battery allows for the storage of save files in SRAM (Static Random Access Memory), which requires power to retain data even when the game is turned off. This design choice ensures that players can continue their adventures without losing progress, especially in RPGs and other long-form games. However, over time, these batteries can deplete, leading to potential data loss if not replaced.