The Brawl era taught players a harsh lesson: Nintendo’s save file management was designed for casual play, not for the hardcore collector. The "no-copy" flag on Brawl save files meant that if your Wii console died—a common occurrence with hardware that was essentially a GameCube with motion controls—your 100% complete file died with it.

Your save file lives on a physical Memory Card inserted into the front of the console.

Similarly, the save file contains sections for stage data, trophy data, and even Spirit data. Each of these sections contains a wealth of information that's used to populate the game world and track player progress.