Said option is not for us But when we give our phone to the service centre for any repairing Then instead of format of our phone,they use this maitance mode after that they can't use our data for their own purpose That's why our data safe and kept on same device This maintance mode introduced by Samsung and copy cat google copied it in its devices
This mode is useful bcz. If you will give your mobile any unauthorized person then you will turn on this mode. If you turn on this mode then the mobile is restart and then you data is not visible any person...
