Democracy works.

The folly of democracy is that it always succumbs to the law of averages. This is good if your average is focused on what is best for the whole, but the tragedy of the commons shows that the individual will most likely be focused on the needs of the individual. So while democracy so far works, it works in a downward spiral because the individuals making the system will not continue to do what is best for the system until the system crashes and they have to rebuild. Once it is rebuilt and improved you can be assured this cycle will recur in a few generations.