Lack of good storyline.

It is interesting even when nothing much happens, which is for most of its 3-hour running time. Read full review

If you're interested in the topic at hand, you should just watch it and judge yourself because the reviews have gone very biased by people that didn't even watch it and just hate (or love) the creator. I liked it, it was well written, narrated, and directed and it was about a topic that interests me.

It is neither dumb nor smart enough to be fun, and spends way too much time with its boring human characters.