The certification of these aircraft is all about establishing the speed, known as Vr, at which, if the correct rotation rate is applied, the aircraft will become airborne without this sort of thiing happening. There is a margin below this to allow for some abuse. The correct rotation rate generally stipulated in Boeing training manuals is 2-3 degrees per second.
This incident would be caused by a too rapid rotation causing the aircraft to strike the tail before it became airborne. Simple.