only restart why?

FLASH INSTRUCTIONS:
1. Choose correct flash file(s).
2. If you have PIT file chosen, then you must check 'Repartition' option.
3. Check flashing options if needed (Repartition, EFS clear, Boot update).
4. Power on the phone in download mode (turn off phone, press vol.down + home + power).
5. Connect the phone to PC with USB cable, install drivers if needed.
6. Press 'Flash' button.

Operation: Flash
Selected model: SM-G570F
Software version: 31.4

File analysis... OK
Total file size: 0xCC5DE8D0 (3269 Mb)
Searching USB Flash interface... COM10 detected
Setup connection... OK
Set PIT file... OK
Reading PIT from phone... OK
Sending sboot.bin... OK
Sending param.bin... OK
Sending cm.bin... OK
Sending boot.img... OK
Sending recovery.img... OK
Sending system.img... OK
Sending userdata.img... OK
Sending modem.bin... OK
Sending cache.img... OK
Sending hidden.img... OK
Flashing done (time - 00:03:38)

Done with Samsung Tool PRO v.31.4