Learn in the textbookReliability Design
DefinitionFool-proof (フールプルーフ) design assumes users will make operating mistakes and either prevents wrong operations or makes them harmless when they happen.
ExplanationDesigners treat people as bound to slip up out of habit or assumption and build in mechanisms that keep those slips from turning straight into accidents or failures. These safeguards usually sit in the parts users touch, such as the shape of a device or the layout of a screen.
AnalogyLike a medicine cap a child cannot easily open, it plans for the user's carelessness from the start.
Memory hookThe proof here is the same as in waterproof: able to withstand something, in this case a novice's handling.