When I was young I believed this was the explanation. I though I was smart and everyone else (with politicians at the top of the list) are stupid. But then I learned humility, and I don't believe in good intentions anymore. They can claim good intentions, and mostly they do, but their motives are far from anything that can be called "good intentions". They are not stupid, you know. They just try hard to look stupid. The more stupid politician looks like, the more chances he is just pretending to avoid responsibility. The purpose of their actions is exactly what they get as the result. If they succeed of course.