It was not the case that one would immediately commit seppuku upon being defeated in battle, as there were many samurai who would go underground (escape and live under a false identity) and plan a comeback.
戦に敗れたから即自決と言うわけではなく、地下に潜り（逃亡し、本当の身分を伏せて生きること）再起を図ろうとする武士も大勢いた。