Why is land mines bad?

They're bad - because you don't know you've stepped on one until it's too late ! If someone throws a hand-grenade at you - you can see it coming and take evasive action. The same applies if you see someone pointing a gun at you. Land mines are buried below the ground - and are triggered by someone stepping on the primer. When the pressure of the foot is released, the primer detonates the explosive. This will at the very least cause the victim to lose a limb, and at worst - their life !