A common mistake that people make when trying to design something completely foolproof is to underestimate the ingenuity of complete fools.
A chair is a very difficult object. A skyscraper is almost easier. That is why Chippendale is famous.
A part of my kind of design and inspiration ethos is that I carry around a leather notebook and I sketch in it, doodle in it, write notes in it, and I put pictures in it.