External drives · Upgrading, transferring and backing up the drive
Why does Transfer Drive ask for my administrator password?
Short answer: Some shortcuts it must update — such as moved apps in your Applications folder — are protected, so macOS needs your administrator password once. If you decline, nothing switches and your current drive stays active.
Switching over means updating the shortcuts that lead to your moved items, and some of them may be in protected places — for example apps you moved out of your Applications folder. macOS requires an administrator password to change those, so Storage Studio asks once at the end.
If you decline, or the final check finds a problem, nothing is switched: your current drive stays active and everything keeps working as before. The new drive keeps its verified copy, so you can try again later.