>Paraphrasing...
>
>Don't bother trying to idiot-proof your applications. They'll just build a better idiot.

Based on actual conversation during a meeting I had some time ago with the managers of some of my users. The crux of the conversation had centered around keeping bad data out of the systems.

Me: So basically what you're asking me to do is idiot proof the systems for you, is that right?

Them: Yes!

Me: OK, it's simple to do: In order to idiot proof the systems, Don't let idiots use them!