Android phone powers on spontaneously during charging I want to charge the phone while it's powered OFF.
But it automatically turns itself ON during charging.  It may be 87% or 90% or 100%.  I don't know the exact reason.
Model = LG-K430n.
I don't like cell phone radiation and I rarely use the phone at all.  I just want it to be OFF most of the time.  This is driving me nuts.
It's by OEM design. See support questions and in particular this one My phone automatically turns on when I connect the charger. Why? which says

Your smartphone will turn on automatically when the charger is connected. Please be assured that it is a sign of normal operation.

And to prevent it from turning on

To charge when your smartphone is off, connect the charger first and press the Power button to turn off your phone. The display will not be turned on.
When the remaining battery is less than 5%, the battery temperature is too high or low, or the smartphone is turned off due to the high temperature, the screen will not turn on.