"Turn off router for 10 seconds" - Quantifiable? [duplicate]

Yes there is.

Any electronics device will have capacitors that will store energy even after you unplug it. You may have noticed when you unplug, say a monitor or TV, the little diode will take another second or two to discharge remaining energy from the capacitors in form of electricity and stop glowing.

This residue energy may not allow memory chips to wipe and you may have problems once your router starts again.

As for the sources - well it's really common sense to someone with basic electronics knowledge, like the sky is blue, water is wet, so I recommend reading about capacitors to see what they do and you will understand it.

The point is that electronics components are far from perfect and any interference may produce unpredictable results.

Ten seconds is an arbitrarily long amount of time, but yes, it does take time for electronic devices to discharge themselves completely because of the capacitance of the circuits within. Some of this capacitance is intentional; some of it is not.

It's impossible to say exactly how much time is needed, as the bleed-off of that capacitance varies with environmental factors like temperature, humidity, and background EMI generated by nearby electronics. The RAM in your computer, for example, can take minutes to discharge fully.

But there is a shortcut. If the router has a button of any kind on it (WPS button, or a reset button), this will usually discharge any residual electric charge immediately. This is because the button places a load on the circuit(s) holding the charge and there is no power going into the device.

In fact, in the old days of parallel ports, this used to be a guaranteed way to correct a stubborn printer. Unplug the printer, unplug the computer, and unplug the parallel cable. Then hit the power button on both devices. Then plug everything back in. Worked every time. Parallel SCSI busses had this problem sometimes too.