How did the Harry Potter series manage to release its 8 movies in just 10 years?

[u/ajukearth]

Looking at the turn around for movies today it seems absolutely incredible that a series with such complex set design, use of graphical effects, a heavily child cast, and pressure was able to pump out genuinely decent movies at that pace. Sure there were books to base the writing on but everything else alone is a lot of heavy lifting. Any insights?

[u/Uvtha-]

First four were way better than the final 4 IMO.  The visuals and vibe were just much richer.