The above poster is right. It's not just some iteration, there is tremendous iteration. The quality that you see comes from iterating until there are no more imperfections and that takes a lot of iterations and a lot of renders. A typical lighter may have 4 shots they are working on at one time, with one finishing about once a week.

So basically the impression from the DVDs is a simplistic fantasy. While the narration says 'it's such a wonderful place' the people working there until 9 every night are thinking 'why is everything broken'.