Night and fatigue could make banzai attacks dangerous

Did banzai attacks work only against poorly trained, poorly motivated, or poorly equipped troops?

They could also exploit tired troops at night: a few seconds of confusion could let attackers close before the defenders organized a response.

A banzai attack relied on shock and on reaching the defenders before they recovered. Tired troops surprised in darkness could be unsure where their commanders and NCOs were or what was happening. Those few seconds allowed attackers to close and inflict casualties. Training and motivation therefore did not remove the danger created by fatigue and surprise.