adb reboot -p usually reboots instead of power-down which it is supposed to When write:

adb reboot -p


I expect the unit to power-down indefinitely. Instead it just reboots automatically, same has having written:

adb reboot


only.

Why is that? What should I write?
Many phones start booting when a power cable is attached. This could be the reason here for the phone rebooting instantly instead of staying off.