[pornel]

This one is funny, but I don't like this saying.

It may be interpreted in a defeatist way that poka-yoke is pointless, because it can always be defeated, but in reality improvements that save almost all "idiots" are still worthwhile.

An interlock in the microwave doors can't stop a better idiot from disassembling it, but it prevents a lot of everyday mistakes, and that's super helpful.

[GuB-42]

I have always thought of this saying as a warning that just because you have implemented a single layer of interlock doesn't mean that you are done.

For instance, let's say you risk electrocuting yourself if you insert a cable the wrong way. So the designers specify a keyed connector, which is the right thing to do. However, it is good to have in mind that some super-idiot will find a way to insert it the wrong way anyways. And as much as you believe in Darwinism, it may still be a good idea to mitigate the risk of electrocution if it happens.