\\\"Powerful Pro Baseball Advance series\\\'s save system in the success mode is a pain. There\\\'s only one save slot each, the file will erase itself when you either clear the story or get a game over, and those games themselves heavily rely on luck, making some of the games\\\' bad ends possible in every corner. Also, every time you load a data, you lose some of your stats.\\\"
Actually, each PPBA gives you three save files. Your file gets deleted when you beat the game or lose, but your character gets moved to \\\"データ\\\" after you beat the game. You can put your character in a custom team.
The only time you ever lose stats after loading a file is when you just turn off the system. To prevent this, just go all the way to the \\\"システム\\\" buttom (far right) and click on \\\"セーブして終了します\\\" (2nd/middle button) and press A button three times.
The only bad ends occur only when you do not meet the minimum requirements to pass each chapter.