charging the memo fhd

[BABA30]

Bought my wife a memo fhd for Christmas and during the setup (reading the instructions) I found that they stated that the charger should NOT be left plugged to the tablet for more than eight hours or damage could result. I ask; what piece of equipment this day and time do you have to remove the charger after a specific time frame. My phone, my laptop, etc. don't state that it must be unplugged after a period of time.

does anyone know for a fact that leaving it plugged up for more than the specified time will in fact damage the unit.

thanks,