This blog post from Digital Amit is an oldie-but-goodie on a quick lesson in simplicity. This could be a useful story for you to tell when motivating your teams to keep it simple!
It compares two approaches to solving the problem of weeding out an empty box of soap on a manufacturing line.
Of course, you might argue that there should be a root cause analysis to find out why the box of soap was empty in the first place, but that spoils the point of the story!